DE102016003464A1 - METHOD AND SYSTEM FOR ADDITIVELY MANUFACTURING USING A HIGH-ENERGY SOURCE AND A HOT WIRE - Google Patents

Abstract

A method and system for producing workpieces using a high intensity energy source to form a puddle and at least one resistance-heated wire heated to or near its melting temperature and deposited into the puddle as droplets.

Description

PRIORITY

The present application is a partial refinement of U.S. Patent Application No. 14 / 163,367, filed January 24, 2014, which is hereby incorporated by reference in its entirety.

TECHNICAL AREA

Certain embodiments relate to additive manufacturing applications. More particularly, certain embodiments relate to a system and method for using a combined flux-cored feed and power source system for additive manufacturing applications.

BACKGROUND

The use of additive manufacturing using various methods has increased in the recent past. However, the known methods have various disadvantages. For example, some processes use metal powders which are generally slow and can lead to significant waste of the powders. Other processes that have arc-based systems are also slow and do not allow the production of high-precision products. Therefore, there is a need for additive manufacturing processes and systems that can operate at high speeds and with a high degree of precision.

Further limitations and disadvantages of conventional, traditional and proposed approaches will be recognized by those skilled in the art by comparing such approaches to embodiments of the present invention set forth in the remainder of the present application with reference to the drawings.

SUMMARY

To solve the problem of providing processes and systems for additive manufacturing which can operate at high speeds and with a high degree of precision, the invention proposes an additive manufacturing system having the features of claim 1 and an additive manufacturing method of claim 7 , Preferred embodiments may be taken from the description, the drawings and / or the dependent claims. Embodiments of the present invention include a system and method for additive manufacturing wherein a high energy device irradiates a surface of a workpiece with a high energy discharge to produce a molten puddle on a surface of the workpiece. A wire feeder leads a wire to the puddle, and a power supply feeds a heating signal into the wire, the heating signal comprising a plurality of current pulses, and wherein each of the current pulses produces a molten droplet at a distal end of the wire which is deposited into the puddle. Each of the current pulses reaches a peak current level after the wire feeder has caused the distal end of the wire to contact the puddle and the warming signal has no current between the multiple current pulses. The wire feeder controls the movement of the wire such that the distal end of the wire does not contact the puddle between successive peak current levels of the current pulses, and the power supply controls the heating current so that no arc exists between the wire and the workpiece during the current pulses Wire and the workpiece during the current pulses arises.

BRIEF DESCRIPTION OF THE DRAWINGS

The above and / or other aspects of the invention will become more apparent by describing in detail exemplary embodiments of the invention with reference to the accompanying drawings, in which:

1 FIG. 12 illustrates a block diagram of an exemplary embodiment of an additive manufacturing system of the present invention; FIG.

2A to 2D illustrate a droplet deposition process according to an exemplary embodiment of the present invention;

3 illustrates another view of a droplet deposition process according to an exemplary embodiment of the present invention;

4A to 4B illustrate representative current waveforms that may be used with embodiments of the present invention;

5 Fig. 10 illustrates a representative embodiment of a voltage and current waveform of the present invention;

6A and 6B illustrate the use of a laser to aid droplet deposition;

7 FIG. 12 illustrates an exemplary embodiment of a wire heating system according to an aspect of the present invention; FIG.

8A FIG. 12 illustrates an exemplary embodiment of a current waveform associated with the system of FIG 7 can be used;

8B FIG. 12 illustrates an exemplary embodiment of current, voltage, wire feed rate, and laser power waveforms for an exemplary embodiment of the present invention; FIG.

9 illustrates another exemplary embodiment of a wire heating system of the present invention;

10 illustrates another exemplary embodiment of the present invention using multiple wires;

11 illustrates another exemplary embodiment of a system of the present invention;

12 Fig. 10 illustrates a power supply system according to an embodiment of the present invention;

13 Figure 1 illustrates an embodiment of a system that uses multiple consumables at one time;

14 illustrates another embodiment of the system of 13 ;

15 illustrates another exemplary embodiment of the in 13 shown system; and

16 Figure 1 illustrates an exemplary embodiment of a non-bonding manufacturing substrate;

17A to 17C illustrate further exemplary embodiments of a non-bonding manufacturing substrate;

18A Figure 1 illustrates one embodiment of a non-bonding substrate with a cooling system;

18B FIG. 12 illustrates an exemplary embodiment of a fabrication stiffening structure that may be used with embodiments of the present invention; FIG.

19A to 19C illustrate exemplary embodiments of braided consumables for additive manufacturing that may be used with the systems described herein;

20A to 20B illustrate an exemplary braided consumable that has become more deformed according to embodiments of the present invention;

20C FIG. 12 illustrates one embodiment of a double wire deposition contact tip assembly as described herein; FIG.

20D Fig. 12 illustrates another exemplary embodiment of a dual wire contact tip of the present invention;

21A and 21B illustrate an exemplary contact tip assembly of the present invention that may be used to deform consumables for delivery during a deposition process;

22 illustrates another exemplary consumable of the present invention;

23 FIG. 12 illustrates another exemplary embodiment of a consumable additive as described herein; FIG. and

24A to 24D illustrate additional exemplary embodiments of additive manufacturing consumables that may be used with embodiments of the present invention.

DETAILED DESCRIPTION

Exemplary embodiments of the invention will now be described below with reference to the accompanying figures. The described exemplary embodiments are intended to assist in the understanding of the invention and are not intended to limit the scope of the invention in any way. Like reference numbers always refer to like elements.

The term "additive manufacturing" is used in the present document in a broad sense and may refer to any application, including building, constructing or creating objects or components.

1 FIG. 12 illustrates a functional block diagram of an exemplary embodiment of a combined flux-cored feeder and power source system. FIG 100 for performing an additive manufacturing. The system 100 contains a laser subsystem that is capable of producing a laser beam 110 on a workpiece 115 to focus around the workpiece 115 to warm up. The laser subsystem is a high-intensity energy source. The Laser subsystem may be any form of high energy laser source including, for example, carbon dioxide, Nd: YAG, Yb disc, YB fiber, fiber transfer or direct diode laser systems. Other embodiments of the system may include at least one of an electron beam, a plasma arc welding subsystem, a gas tungsten arc welding subsystem, a gas metal arc welding subsystem, a flux cored arc welding subsystem, and a subpowder. Arc welding subsystem to serve as the high-intensity power source. The following specification repeatedly refers to the laser system, the laser beam and the laser power supply; however, it should be understood that these references are merely exemplary in nature, as any high-intensity energy source may be used. For example, a high intensity energy source can provide at least 500 W / cm ² . The laser subsystem includes a laser device 120 and a laser power supply 130 that are operatively connected to each other. The laser power supply 130 provides the energy to operate the laser device 120 ,

The system 100 Also includes a hot fill wire feeder subsystem capable of having at least one ohmic flux cored wire 140 to provide a contact with the workpiece 115 near the laser beam 110 manufacture. Of course, it goes without saying that with the mention of the workpiece 115 in the present text, the molten puddle as part of the workpiece 115 is viewed, so the reference to a contact with the workpiece 115 also contains a contact with the puddle. The hot fill wire feeder subsystem includes a cored wire feeder 150 , a contact tube 160 and a power supply 170 , During operation, the cored wire becomes 140 by electricity from the power supply 170 between the contact tube 160 and the workpiece 115 is actively connected, resistance heated. According to one embodiment of the present invention is the power supply 170 a pulsed DC power supply, although AC or other types of power supplies are also possible. The wire 140 is from the Fülldrahtzufuhrvorrichtung 150 through the contact tube 160 in the direction of the workpiece 115 fed and extends over the pipe 160 out. The extension section of the wire 140 is so resistance heated that the extension portion approaches or reaches the melting point before it contacts a weld puddle on the workpiece. The laser beam 110 serves to melt a part of the base metal of the workpiece 115 to form a sweat puddle, and may also melt the wire 140 on the workpiece 115 be used. The power supply 170 provides the energy needed to fill the flux wire 140 widerstandszuschmelzen. As will be explained in more detail below, provides the power supply 170 in some embodiments, the total energy required, while in other embodiments, the bearing or other high-energy heat source may provide some of the energy. The feeder subsystem may, according to certain other embodiments of the present invention, be capable of simultaneously providing one or more wires. This will be discussed in more detail below.

The system 100 further includes a motion control subsystem capable of the laser beam 110 (the energy source) and the ohmic flux-cored wire 140 in the same direction 125 along the workpiece 115 (at least in the relative sense) to move in such a way that the laser beam 110 and the ohmic flux-cored wire 140 stay in a fixed relationship. According to various embodiments, the relative movement between the workpiece 115 and the laser / wire combination can be achieved by holding the workpiece 115 actually moved or by the laser device 120 and the wire feeder subsystem moves. In 1 The motion control subsystem includes a motion control unit 180 that with a robot 190 is actively connected. The motion control unit 180 controls the movement of the robot 190 , The robot 190 is with the workpiece 115 operatively connected (eg mechanically attached) to the workpiece 115 so in the direction 125 to move that, the laser beam 110 and the wire 140 practically on the workpiece 115 move along. According to an alternative embodiment of the present invention, the laser device 110 and the contact tube 160 be integrated in a single head. The head can travel along the workpiece via a motion control subsystem operatively connected to the head 115 to be moved.

In general, there are various methods of how to move a high intensity power source and a hot wire relative to a workpiece. For example, when the workpiece is round, the high intensity energy source and the hot wire may be stationary, and the workpiece may be rotated under the high intensity energy source and the hot wire. Alternatively, a robotic arm or linear pulling device may move parallel to the round workpiece, and while the workpiece is being rotated, the high intensity energy source and hot wire may move continuously or incrementally once per revolution, for example material onto the surface of the round workpiece apply. If the workpiece is flat or at least not round, the workpiece can be moved under the high intensity energy source and the hot wire as in 1 shown. However, a robotic arm or device, or even a carriage mounted on a carrier, may also be used to move a high intensity power source and a hot wire head relative to the workpiece.

The system 100 further includes a sense and current control subsystem 195 that with the workpiece 115 and the contact tube 160 operatively connected (ie practically with the output of the hot wire power supply 170 connected) and is capable of a potential difference (ie, a voltage V) between the workpiece 115 and the hot wire 140 and a current (I) through the workpiece 115 and the hot wire 140 to eat. The sensing and current control subsystem 195 Further, it may be capable of calculating a resistance value (R = V / I) and / or a power value (P = V · I) from the measured voltage and the measured current. In general, if the hot wire 140 in contact with the workpiece 115 stands, the potential difference between the hot wire 140 and the workpiece 115 zero volts or very close to zero volts. As a result, the sense and current control subsystem 195 sensing when the ohmic flux cored wire 140 in contact with the workpiece 115 stands, and is connected to the power supply 170 operatively connected to further be able to control the current flow through the ohmic flux-cored wire 140 in response to sensing, as described in greater detail below. According to another embodiment of the present invention, the sense and current control unit 195 an integral part of the power supply 170 be.

According to an embodiment of the present invention, the motion control unit 180 further with the laser power supply 130 and / or the sense and current control unit 195 be actively connected. In this way, the motion control unit can 180 and the laser power supply 130 communicate with each other so that the laser power supply 130 knows when the workpiece 115 moves, and thus the motion control unit 180 knows if the laser device 120 is active. Similarly, the motion control unit 180 and the sense and current control unit 195 communicate with each other in this way, so that the sensing and power control unit 195 knows when the workpiece 115 moves, and thus the motion control unit 180 knows when the hot fill wire feeder subsystem is active. Such communication can be used for activities between the various subsystems of the system 100 to coordinate.

As is well known, additive manufacturing is a process in which a material is deposited on a workpiece to obtain a desired product. In some applications, the product can be quite complex. However, known methods and systems used for additive manufacturing are generally slow and have limited performance. Embodiments of the present invention address these problem areas by providing a fast and high-precision additive manufacturing method and system.

This in 1 shown system 100 is such an exemplary system where the wire 140 repeatedly melted into droplets and deposited on the workpiece to produce the desired shape. This process is exemplary in the 2A - 2D shown. As shown in these figures. As in 2A Shown is a surface of the workpiece by the laser beam 110 (or another heat source) irradiated while the wire 140 not in contact with the workpiece. The beam 110 creates a melt puddle A on the surface of the workpiece. In most applications, the puddle A has a small area, and the penetration depth is not that required for other operations, such as welding or joining. Rather, the puddle A is created to prepare the surface of the workpiece, a droplet of the wire 140 to receive and make a sufficient bond with him. That's why the beam density of the beam 110 be such that only a small puddle is created on the workpiece without causing too much heat input into the workpiece or producing too large a puddle. When creating the puddle, a droplet D is formed at the distal end of the wire 140 formed while the wire is pushed into the puddle A to make contact with the puddle A; please refer 2 B , After contact, the droplet D is deposited on the puddle A and the workpiece (see 2C ). This process is repeated to produce a desired workpiece. In 2D an optional step is shown in which the beam 110 is directed to the deposited droplet D, after moving away from the wire 140 has separated. In such embodiments, the beam 110 be used to smooth the workpiece surface and / or supply additional heat, so that the droplet D can be fully integrated into the workpiece. Furthermore, the jet can be used to additionally shape the workpiece.

3 shows an exemplary deposition process of the droplet D from the wire 140 , The picture on the left edge of 3 shows the wire 140 how he makes contact with the workpiece. This contact is made by the power supply 170 then detects a heating current in the wire 140 feeds the wire to, or near, a, melting temperature for the wire 140 to heat. The detection circuit used to make the contact between the workpiece and the wire 140 can be so constructed and operate as known detection circuits used in welding power supplies, so that a detailed explanation of the operation and construction of the circuit can be omitted in the present document. The heating current of the power supply 170 is raised very quickly to get the energy needed to melt the droplet D from the end of the wire 140 provide. However, the current is carefully controlled so that there is no arc between the wire 140 and the workpiece is created. The emergence of an arc could turn out to be destructive to the workpiece and is therefore undesirable. Therefore, the current must be controlled in such a way (as will be explained further below) that the occurrence of an arc is prevented.

We return 3 back. The wire 140 makes contact with the workpiece, and the power supply 170 provides a melt stream (1). In some example embodiments, an Open Circuit Voltage (OCV) may be before contact with the wire 140 be created. After contact, the current is quickly raised to the end of the wire 140 to melt and produce a droplet D to be deposited (2). The electricity also causes the wire 140 just above the droplet D pinch off, so that the droplet D from the wire 140 can replace (3). However, the current is controlled so that while the wire is 140 pinch off, the power is either turned off or significantly reduced, so that when the wire 140 separated from the droplet D, no arc between the wire 140 and the workpiece (4) arises. In some example embodiments, the wire may be 140 during and just before breaking the connection between the droplet D and the wire 140 retracted away from the workpiece. Because the droplet D is in contact with the puddle, the surface tension of the puddle helps in detaching the droplet from the wire 140 , Once the droplet from the wire 140 was disconnected, the wire becomes 140 pushed forward to repeat the process and deposit another droplet. The wire 140 may be advanced at the same position and / or the next droplet may be deposited at any desired position.

As previously discussed, the laser beam can 110 may also be used after the droplet D has been deposited on the workpiece to flatten or otherwise shape the workpiece after deposition. Furthermore, the beam 110 also be used during the deposition process. That is, in some example embodiments, the beam 110 be used for heat to the wire 140 to cause the formation of the droplet and / or the separation of the droplet D from the wire 140 to support. This will be discussed below.

Let us now turn to that 4A and 4B , which each show exemplary current waveforms that may be used with exemplary embodiments of the present invention. In 4A , as can be seen, has the waveform 400 several pulses 401 where each pulse is the transmission of a droplet D from the wire 140 represents. A current pulse 401 is started at the time where the wire 140 makes a contact. The current is then using a rising section 402 on a peak current level 401 increased, which is close to the separation between the wire 140 and the droplet D enters. In this embodiment, the current becomes during the rising portion 402 continuously larger to cause the formation of the droplet and to cause pinch-off in the wire before separation. Before the separation of the droplet D, the flow during a lowering section 404 rapidly reduced, so that when the separation takes place, no arc is formed. In the waveform 400 from 4A the power is turned off and drops to zero. However, in other exemplary embodiments of the present invention, the current may be lowered to a lower isolation level and need not be completely turned off until the isolation occurs. In such embodiments, the lower separation current level adds to the wire 140 Heat is further added, thereby assisting the detachment of the droplet D.

4B shows another exemplary embodiment of a current waveform 410 , However, in this embodiment, the pulses 411 a rise section 402 using several different slew rate sections as shown. In the illustrated embodiment, the riser section uses 402 three different rates of increase 402A . 402B and 402C before the separation of the droplet D. The first rate of increase 402A is a very steep and fast current increase to the wire 140 warm up quickly to start the melting process as soon as possible. After the current is a first level 405 has reached, the rate of increase is a second rate of increase 402B changed, which is smaller than the first rate of increase. In some example embodiments, the first current level is in a range of 35 to 60% of the peak current level 413 for the impulse. The rate of increase 402B is less than the initial rate of increase 402A to help control the flow and prevent the formation of arcs or micro-arcs. In the shown Embodiment, the second rate of increase is maintained until the droplet D at the distal end of the wire 140 begins to form. In the illustrated embodiment, as the droplet D starts to form, the rate of current rise again becomes a third rate of increase 402C changed smaller than the second rate of increase 402B is. Again, reducing the slew rate serves to improve the control of the current to prevent the unwanted generation of an arc. If the current increased too rapidly, it may be difficult (due to various problems, such as system inductance) to rapidly lower the current when the separation is detected and to prevent the generation of an arc. In some example embodiments, the transition point is located 407 between the second and third slew rates in a range of 50 to 80% of the peak current level 413 of the impulse 411 , Like the impulses in 4A the current is significantly reduced when the separation of the droplet is detected, which will be explained in detail below. It is also to be noted that other embodiments of the present invention may utilize other slew rate profiles without departing from the scope or spirit of the present invention. For example, the pulses may have two different slew rate sections or may have more than three. Furthermore, the pulses can use a slope that is constantly changing. For example, the current may follow an inverse parabolic curve to the peak current level, or may use a combination of different configurations, with a constant slew rate from wire contact to the first current level 405 is used and then from this point an inverse parabolic curve can be used.

As explained in this document, the peak current levels of the pulses 401 / 411 below an arc generation level, but be sufficient to melt the droplet D during each pulse. Exemplary embodiments of the present invention may utilize various peak current level control methodologies. In some example embodiments, the peak current level may be a peak current threshold determined by various user input parameters that are input prior to the additive operation. Such parameters include wire type, wire diameter, wire type (with core or solid wire) and droplets per inch (DPI). Of course, other parameters can be used. Upon receipt of this input information may be the power supply 170 and / or the control unit 195 use various control methodologies, such as a look-up table, and determine a peak current value for the operation. Alternatively, the power supply 170 Output current, voltage and / or power from the power supply 170 monitor to determine when the disconnection will take place and to control the current accordingly. For example, dv / dt, di / dt, and / or dp / dt may be monitored (using a lookahead circuit or the like), and if it is determined that the separation is taking place, then the power will be turned off or reduced. This will be explained in more detail below.

The following is a discussion of the use and operation of exemplary embodiments of the present invention. At the beginning of an additive manufacturing process can be the power supply 170 a sense voltage between the wire 140 and a workpiece 115 via the power source 170 invest. The sensing voltage can be through the power supply 170 under the control of the sense and current control unit 195 be created. In some embodiments, the applied sense voltage does not provide enough energy to the wire 140 to heat appreciably. When the sensing voltage is applied, the distal end of the wire becomes 140 in the direction of the workpiece 115 advance pushed. The laser 120 then send a beam 110 off to the surface of the workpiece 115 to warm and form a puddle to the wire 140 to recieve. The feed is through the wire feeder 150 executed, and the contact with the workpiece is sensed when the distal end of the wire 140 first contact with the workpiece 115 manufactures. For example, the sense and current control unit 195 the hot wire power supply 170 instruct a very low current level (for example 3 to 5 A) through the hot wire 140 supply. Such sensing may be provided by the sense and current control unit 195 by making a potential difference of about zero volts (for example 0.4 V) between the flux cored wire 140 (for example via the contact tube 160 ) and the workpiece 115 measures. If the distal end of the filler wire 140 with the workpiece 115 is short circuited (ie makes contact with the workpiece), there may not be a significant voltage level (above zero volts) between the flux cored wire 140 and the workpiece 115 ,

After contact, the power source 170 in response to sensing over a defined time interval (eg, several milliseconds). Then the power source 170 be turned on again at the end of the defined time interval to a heating current through the wire 140 to flow. In addition, after the contact has been sensed, the beam can 110 be turned off so as not to heat too much into the puddle or the workpiece 115 arrives. In In some embodiments, the laser beam 110 stay on to help warm and separate the droplet D. This will be discussed in more detail below.

In some example embodiments of the present invention, the process may include advancing the wire 140 to stop in response to the sensing, advancing the wire 140 at the end of the defined time interval to start again (ie advance again), and verify that the distal end of the filler wire 140 still in contact with the workpiece 115 is before the heating current is applied or after the heating current is applied and the droplet D is formed. The sensing and power control unit 195 can the wire feeder 150 instruct, stop feeding, and can system 100 instruct to wait (for example, several milliseconds). In such an embodiment, the sense and current control unit is 195 with the wire feeder 150 operatively connected to the wire feeder 150 instruct, start and stop. The sensing and power control unit 195 can the power supply 170 instruct the heating current pulses to heat the wire 140 as described above, and this process can be repeated to deposit multiple droplets on a workpiece.

During operation, the high-intensity energy source (for example, the laser device 120 ) and the wire 140 along a workpiece 115 be moved to produce the droplets as desired. The motion control unit 180 instructs the robot 190 on, the workpiece 115 relative to the laser beam 110 and the wire 140 to move. The laser power supply 130 Provides the energy to the laser device 120 to operate and the laser beam 110 to build. In other embodiments, the laser device includes 120 an optic that can be adjusted to the shape of the laser beam 110 to change on the impact surface of the workpiece. Embodiments may use the beam shape to control the shape of the deposition process. That is, by using a jet having a rectangular, elliptic or oval shape, a relatively narrow deposit can be made, thereby forming a thin-edged structure. Furthermore, the jet shape can be used to shape the deposit after the droplet has separated from the consumable.

As discussed above, the pulse current is turned off or significantly reduced when it is determined that the separation between the wire 140 and the droplet D is imminent. This can be achieved in different ways. For example, such sensing may be with a lookahead circuit within the sense and current controller 195 which is a rate of change of a potential difference between the wire 140 and the workpiece 115 (dv / dt), a current through the wire 140 and the workpiece 115 (di / dt), a resistance between the wire 140 and the workpiece 115 (dr / dt) or a power through the wire 140 and the workpiece 115 (dp / dt) measures. When the rate of change exceeds a predetermined value, the sense and current control unit predicts 195 formally, that a loss of contact is imminent. Such look-ahead circuits are familiar to those skilled in the art of arc welding, and their structure and operation need not be described in detail in this document.

If the distal end of the wire 140 becomes highly molten due to heating, so the distal end starts from the wire 140 on the workpiece 115 pinch off. For example, at this moment, the potential difference or stress increases because the cross-section of the distal end of the wire rapidly decreases as it pinches off. That's what the system can do 100 by anticipating such a rate of change, when the distal end is about to strangle and contact the workpiece 115 to lose.

As previously explained, when the separation of the droplet is sensed, the current through the power supply can 170 switched off or significantly reduced. For example, in some example embodiments, the current is reduced to a range of 95 to 85% of the peak current value of the pulses. In exemplary embodiments, this power reduction occurs prior to the separation between the wire and the puddle.

For example, illustrated 5 an exemplary embodiment of a pair of voltage and current waveforms 510 respectively. 520 associated with an additive manufacturing process of the present application. The voltage waveform 510 is through the sensing and power control unit 195 between the contact tube 160 and the workpiece 115 measured. The current waveform 520 is from the sensing and power control unit 195 through the wire 140 and the workpiece 115 measured.

Whenever the distal end of the wire 140 just before that is the contact with the workpiece 115 losing exceeds the rate of change of the voltage waveform 510 (ie, dv / dt) a predetermined threshold, indicating that pinching is imminent (see the descent at point 511 the waveform 510 ). Instead As alternatives, a rate of change of the current through the wire may be used 140 and the workpiece 115 (di / dt), a rate of change of resistance between the wire 140 and the workpiece 115 (dr / dt) or a rate of change of power through the wire 140 and the workpiece 115 (dp / dt) are used to indicate that pinching is imminent. Such rate of change prediction techniques are familiar to those skilled in the art. At this moment, the sensing and current control unit points 195 the power supply 170 on, the flow of current through the wire 140 switch off (or at least significantly reduce).

When the sensing and power control unit 195 feels that the distal end of the filler wire 140 after a time interval 530 again a good contact with the workpiece 115 has (for example, the voltage level at point 512 falls to about zero volts), so the sense and current control unit 195 the power supply 170 on, the current flow through the ohmic flux-cored wire 140 in the direction of a predetermined output level 550 raise (see rise 525 ). The time interval 530 may be a predetermined time interval. In accordance with an embodiment of the present invention, the increase begins at a set point value 540 , This process is repeated while the energy source 120 and the wire 140 relative to the workpiece 115 move and while the wire 140 through the wire feeder 150 in the direction of the workpiece 115 is advanced to separate droplets at the desired locations. This will prevent an arc between the distal end of the wire 140 and the workpiece 115 forms. Increasing the heating current helps to prevent a rate of change of the voltage from being unintentionally interpreted as a pinch condition or an arcing condition when no such condition exists. Any large change in current can cause a faulty voltage reading to occur due to the inductance in the heating circuit. As the current is gradually increased, the effect of inductance is reduced.

As explained above, the power supply feeds 170 a heating current in the filler wire 140 one. The current flows from the contact tip 160 to the wire 140 and then into the workpiece. This resistance heating current causes the wire 140 between the top 160 and the workpiece at a temperature at or near the melting temperature of the filler wire used 140 reached. Of course, the heat used to reach the melting temperature of the filler wire varies 140 is needed, depending on the size and chemical composition of the wire 140 , Accordingly, the heat varies to reach the desired temperature of the wire during manufacture, depending on the wire 140 , As will be discussed in more detail below, the desired operating temperature for the flux-cored wire may be data entry into the system such that the desired wire temperature is maintained during manufacture. In any case, the temperature of the wire should be chosen so that the wire 140 can separate a droplet into the puddle.

In exemplary embodiments of the present invention, the power supply is 170 a stream comprising at least a portion of the distal end of the wire 140 to a temperature of or above 90% of its melting temperature. If, for example, a cored wire 140 with a melting temperature of about 2,000 ° F, the temperature of the wire at the moment of contact may be about 1,800 ° F. Of course, it will be understood that the particular melting temperatures and desired operating temperatures are at least commensurate with the alloy, composition, diameter, and feed rate of the filler wire 140 vary. In further exemplary embodiments, portions of the wire are maintained at a temperature of the wire that is at or above 95% of its melting temperature. Of course, in some embodiments, the distal end of the wire is heated to at least 99% of its melting temperature by the heating current. Thus, when the heated droplet is in contact with the molten puddle generated by the laser, the heat from the puddle may add additional heat to the wire 140 lead so completely the molten droplet at the end of the wire 140 so that the droplet adheres to the puddle and stays there when the wire 140 is withdrawn. By holding the filler wire 140 at a temperature close to or at its melting temperature becomes the wire 140 in a simple way in by the heat source or the laser 120 produced puddle melted or consumed. That is, the wire 140 has a temperature that does not cause any appreciable quenching of the puddle when the wire 140 makes contact with the puddle. Due to the high temperature of the wire 140 The wire melts quickly when it comes in contact with the puddle. In other exemplary embodiments, the wire may be heated to or above 75% of its melting temperature. However, when heated to near 75%, it is likely that additional heating will be needed to make the droplet sufficiently molten for transfer, which will be discussed in more detail below.

As previously described, in some example embodiments, the complete melting of the wire 140 only by the entry of the wire 140 done in the puddle become. However, the wire can 140 in other exemplary embodiments also by a combination of the heating flow, the puddle and the laser beam 110 that is on a section of the wire 140 hits, completely melted. That is, heating or melting the wire 140 can through the laser beam 110 be supported in such a way that the beam 110 for heating the wire 140 contributes. Because, however, many cored wires 140 made of materials that can reflect should, if a reflective laser is used, the wire 140 be heated to a temperature such that its surface reflectivity is reduced, so that the beam 110 for heating or melting the wire 140 can contribute. In exemplary embodiments of this configuration, the wire overlap 140 and the beam 110 at the point where the wire 140 enters the puddle. This will be in the 6A and 6B shown.

As in 6A In some example embodiments, the beam may be shown 110 used for the deposition of droplets D on the workpiece 115 to support. That is, the beam 110 Can be used to heat to the distal end of the wire 140 to create the molten droplet. In such embodiments, the heating current from the power supply may be maintained at a level well below an arc generation level, thereby ensuring that no arc is generated but proper droplet transfer can be achieved. In such embodiments, the beam may be directed to strike only the droplet D; or in other embodiments, the beam 110 large enough or shaped or rastered to impinge at least a portion of the droplet and at least a portion of the puddle to further add heat to the puddle to receive the droplet D. In exemplary embodiments, the energy density of the beam is 110 during this phase of the process is usually lower than the energy density of the beam when it is used to puddle the workpiece 115 to create.

6B shows further exemplary embodiments of the present invention, wherein the beam 110 on the wire 140 just above the droplet to support its separation from the wire. In such embodiments, when sensed or determined, the wire becomes 140 strangling over the droplet, a jet 110 on the wire at the junction between the droplet D and the wire 140 directed so that the beam 110 when separating the two helps. Such embodiments help to prevent an arc from arising because it is not necessary to use the heating current to control the separation. In some example embodiments, the beam 110 from the same laser 120 come, which is used to create the original puddle. However, in other embodiments, the beam may be in 6B are also emitted by a second separate laser, which is also by the control unit 195 is controlled. That is, in such embodiments, when the control unit and / or the power supply detect the formation of a droplet or the imminent separation of the droplet D, the output current of the power supply can 170 be lowered while the laser beam on the wire 140 is directed to bring about the desired separation.

Let us turn now 7 to where an exemplary embodiment of a heating system 700 and a contact tip assembly 707 is shown. It is generally noted that embodiments of the present invention are contact tips 160 and to use resistance heating systems known with respect to hot wire or some welding systems without departing from the spirit or scope of the present invention. However, in other exemplary embodiments, a system 700 , as in 7 shown to be used. In this system 700 For example, the contact tip assembly consists of two conductive sections 701 and 703 passing through an insulating section 705 , which may be made of any dielectric material, are electrically isolated from each other. Of course, in other embodiments, the insulating portion may be omitted as long as the tip portions 701 and 703 are electrically isolated from each other. The system 700 also includes a switching circuit 710 which is the current path to or from the power supply 170 between the contact tip section 701 and the workpiece 115 switches. In some embodiments, it may be desirable to use the wire 140 during the manufacturing process to maintain a threshold temperature while the wire 140 not with the workpiece 115 in contact. Without the wire 140 with the workpiece 115 is in contact (for example, during repositioning), no current flows through the wire 140 so that the resistance heating stops. Of course, there may still be residual heat, but it can subside quickly. This embodiment allows continuous heating of the wire 140 even if he is not in contact with the workpiece 115 stands. As shown, a lead wire is from the power supply to the top section 703 the contact tip assembly 707 coupled. During operation, when the wire is 140 is in contact with the workpiece, the switch 710 positioned so that the current path from the top section 703 through the wire 140 and the workpiece leads and to the power supply 170 returns (Dash line in the switch 710 ). But if the droplet D from the wire 140 separates and the contact with the workpiece 115 is interrupted, then the switch 710 Tilted so that the current path from the contact tip section 703 to the contact tip section 701 and back to the power supply 170 leads. Thereby, at least a portion of the heating current may flow through the wire to further resistively heat the wire at a certain background heating level. Such a configuration allows the wire to be heated more quickly to its desired deposition level. This is especially the case if there was a long time between droplet deposits during which the wire could cool off. Therefore, in exemplary embodiments, the power supply 170 one or more current pulses (as generally described in this document) to separate droplets when the switch 710 located in a first position (first current path), which directs the current through the workpiece, and then gives the power supply 170 a background or heating current (which may be, for example, a constant current) when the switch is in a second position (second current path) that drives the current through both sections 701 / 703 the contact tip to keep the wire in a heated state between droplet transfers. In some embodiments, the switch may toggle between the individual droplet transfer pulses, while in other embodiments the switch may switch to multiple droplet transfer pulses. In exemplary embodiments, the heating current level is selected as a level that maintains the wire at a desired (non-melt) temperature. If the temperature is too high, it may be difficult to push the wire to the puddle. In some exemplary embodiments, the heating current is in a range of 10 to 70% of a peak current level achieved during the droplet transfer pulses.

It is noted that in 7 the desk 710 outside the power supply 170 is shown. However, this illustration is only for clarity, and the switch can also be within the power supply 170 be arranged. Alternatively, the switch may also be within the contact tip assembly 707 are located. The insulating section 705 can be made of any insulating material or simply an insulating gap between the components 701 and 703 be. Depending on the desired configuration, the switch can be controlled by the control unit 195 (as shown) or can be controlled directly by the power supply 170 to be controlled.

In other exemplary embodiments, a wire preheating device may be upstream of the assembly 707 be positioned that the wire 140 preheats, before going to the top 707 entry. For example, the preheater may be an induction heating device that does not conduct current through the wire 140 requires the wire 140 to warm up. Of course, resistance heating systems can also be used. This preheater can be used to maintain the wire at a temperature as described above. Furthermore, preheating can also be used to remove any unwanted moisture from the wire 140 before it is separated (which is especially important when Ti is used). Such preheat systems are well known and need not be described in detail. The preheater can be adjusted to hold the wire 140 heated to a predetermined temperature before the wire in the tip assembly 707 enters, reducing the power from the power supply 170 can be used to supply enough power to complete the deposition process. It should be noted that the preheater the wire 140 should heat to a level of the wire 140 conditioned so that the wire 140 properly through the top 707 can be pushed. That is, if the wire 140 Too warm, so it can become overly flexible, which is the response of the wire 140 can interfere with pushing.

8A shows an exemplary manufacturing current waveform 800 that with the system 700 in 7 can be used. In 8A is a base current waveform 800 which includes two components: a pulse section 801 and a background section 803 , The pulse section consists of current pulses used to deposit droplets as discussed in this document. During these pulses, the current from the tip section 703 through the workpiece 115 directed. However, the current during the background portion becomes from the tip portion 703 to the section 701 directed to the wire 140 to heat up when not in contact with the workpiece 115 stands. Of course, it should be noted that the connections of the contact tip sections 701 / 703 to the positive and negative power supply outlets, as in 7 shown, are exemplary and that the connections according to the desired system device and performance can also be reversed. As previously explained, the background current level becomes 803 between impulses 801 used to keep the wire between droplet deposits at a holding temperature. In some exemplary embodiments of the present invention, the background current holds the wire 140 at a temperature that is in one range from 40 to 90% of the melting temperature of the wire 140 lies. In other exemplary embodiments, the power holds 803 the wire 140 at a temperature in the range of 50 to 80% of the melting temperature of the wire 140 ,

It should also be noted that it may not be desirable or necessary to constantly switch between the individual pulses 801 to switch to the background current. This could be especially true during a high droplet deposition rate. That is, during a high droplet deposition rate, the wire becomes 140 held between the droplets at a high temperature level. Therefore, in some example embodiments, switching to the background heating current (as described above) occurs only after the lapse of a period of time or when the duration between droplet pulses exceeds a threshold time. For example, the system uses 700 in some embodiments, when the time between pulses is to exceed 1 second, the switching and the background heating current are as described above. That is, if the manufacturing method used has a pulse frequency above a certain threshold frequency, the switching described above is used. In exemplary embodiments of the present invention, this threshold is in a range of 0.5 to 2.5 s between pulses. In other embodiments, the system may 700 a timer (within the control unit 195 and / or the power supply 170 ), which monitors the time between pulses, and when the time exceeds a threshold amount, the switching and the background heating current are used as described above. If, for example, the system 700 determines that a latency between pulses has exceeded a threshold time limit (for example 1 s), the background heating current is used for the wire 140 to keep at a desired temperature. Such an embodiment may be used in embodiments where the set threshold time has expired; that is, the system 700 determines in real time that the time limit has expired, or can be used when the system 700 predicts that the next impulse will not occur before the expiration of the time limit. If, for example, the system 700 (for example, the control unit 195 ) determines that the next pulse will not occur before the expiration of the time limit (for example due to movement of the workpiece) 115 and / or the wire 140 ), so the system can 700 immediately initiate the switching and the background heating current as described above. In exemplary embodiments of the present invention, this duration threshold is in the range of 0.5 to 2.5 seconds.

8B FIG. 12 shows exemplary waveforms that may be used with exemplary embodiments of the present invention to deposit a droplet as described herein. The exemplary waveforms are for transmission of a single droplet according to embodiments of the present invention. The waveforms shown are for laser power 810 , Wire feed speed 820 , additive wire heating current 830 and tension 840 , It should be understood that the waveforms shown are intended to be exemplary only and that other embodiments of the present invention may use other waveforms having different characteristics than those shown or described herein. As shown, the droplet transfer cycle begins at 811 where the laser power is directed to the workpiece and to a peak laser power level 813 is increased 812 , After a period of time Tp, the laser produces a puddle on the workpiece at point 814 , At this point, the wire feeder begins to move the additive wire toward the puddle. The wire feed speed increases 821 on a spike wire feed speed 822 after the puddle 814 was generated. In exemplary embodiments of the present invention, the wire feed speed reaches its peak level 822 at about the same time the distal end of the wire makes contact with the puddle 821 ' manufactures. However, in other exemplary embodiments, the wire feed speed may be at its peak level 822 reach before the wire makes contact. As shown, at the same time as the wire feed process begins, an open circuit voltage is applied to the wire 841 applied so that it has a peak voltage level 842 reached at one point before the wire makes contact with the puddle. In addition, when the wire makes contact with the puddle, the heating current begins 830 to flow (at point 831 ), and the tension 840 begins to fall 843 , The voltage drops to a level 844 which is under an arc detection voltage 848 above which it is determined that an arc would be generated.

After the wire has made contact with the puddle, the laser power becomes 810 , the wire feed speed 820 and the stream 830 over a period Ta, during which a droplet of the wire is deposited in the puddle, kept at their respective peak levels. After expiration of the deposition period Ta (at 815 ), which may have a predetermined period of time controlled by the heating power supply (for example, using a timer circuit), the laser power becomes along with the wire feeding speed 823 lowered 816 , The heating current 830 becomes after the expiration of the period Ta (highest point 834 ) still over one Period at its peak level 833 while reducing the laser power and the wire feeding speed. This helps in separating the droplet from the wire. After the droplet addition period Ta, a wire retreat period Tr starts. After the stream 830 his lowering 835 starts (start at point 834 ), the wire feed speed is reduced to zero (at point 827 ), and the wire feeder is caused to cause the wire 824 with a tip retraction speed 825 withdraw. In addition, the electricity 830 during the withdrawal period to a backflow level 836 which is used to rewind the wire as it is withdrawn from the puddle. During the wire retraction period Tr, the current becomes 830 on the backflow level 836 held until the voltage at point 845 the arc detection voltage level 848 This happens when the wire separates from the puddle (causing the current to drop and the voltage rises). When the voltage level 848 is reached, an arc suppression routine 847 initiated to prevent the occurrence of an arc. During this time, the voltage rises to a peak level 846 ,

The arc detection voltage level 848 is a predetermined level used by the power supply and / or the system controller to ensure that there is no arc between the retracting wire and the workpiece. The arc detection voltage level 848 is set by the power supply and / or the system controller based on various user inputs, such as wire type, wire diameter, workpiece material type, droplet-per-inch input, droplet-per-minute input, etc.

When the arc detection voltage level 848 is reached (at 845 ), so will the electricity 830 switched off by the power supply ( 837 ), and retraction of the wire is stopped ( 826 ), and the droplet transfer cycle ends at point 817 when the electricity 830 and the wire feed speed 820 reach 0 each. In the embodiment shown, it is also shown that the laser power 810 at the end of the cycle at point 817 is switched off. In other exemplary embodiments, the laser power becomes 810 shut off at the time when the arc voltage threshold 848 reached (at point 845 ). This cycle is then repeated over several droplet deposits.

In some exemplary embodiments (not shown), a laser power pulse may be initiated between droplet transfer cycles (as in FIG 8B shown) to assist in smoothing the workpiece or otherwise supplying energy to the workpiece between droplet transfers. For example, a laser power pulse may be initiated between each droplet transfer cycle, or in other embodiments, a laser power pulse may be initiated as needed after a number n of droplet transfer cycles.

9 shows another exemplary system 900 of the present invention. The system 900 includes a background power supply 170 ' and a pulsation power supply 170 , The operation of this system is very similar to that discussed above except that the background heating current is provided by a separate power supply 170 ' is supplied. Therefore, in some embodiments, the background power supply 170 ' provide a constant heating current during manufacture, and it is not necessary to carry out the switching discussed above. The pulsation power supply 170 operates as described elsewhere herein, except that thanks to the additional heating or additional current generated by the power supply 170 ' is provided, their peak output current can be reduced. In such embodiments, the degree of control or precision with the pulsed power supply 170 increase. That is, the pulse power supply 170 thanks to the lower power requirement in the power supply 170 reach their peak pulse level more quickly. Of course, the same applies to decreasing electricity. Each of the power supplies 170 / 170 ' can through the control unit 195 or can be configured in a master / slave relationship, which is well known. Furthermore, while these power supplies are shown separately for clarity, they may be housed within a single unit without departing from the spirit or scope of the present invention.

It is also in 9 another contact tip assembly 900 shown the conductive sections 901 and 905 and an insulating section 903 having. In this embodiment, the conductive portion 905 configured so that the heating current is as close as possible to the exposed distal end of the wire 140 is transmitted. Such a configuration helps to ensure that the heating of the wire is kept as close as possible to the distal end, thereby optimizing the effects of background heating. In further embodiments, the board X becomes the distal end of the wire 140 from the contact point 910 kept at a minimum distance. If the board X is held upright for too long, the heating effects of the background heating current may be impaired. Therefore, in some example embodiments, the Board X in the range of 0.1 to 0.5 inches maintained. In other exemplary embodiments, the board is maintained in the range of 0.2 to 0.4 inches. Furthermore, in other exemplary embodiments (to realize further advantages of background heating), the wire is used 140 between droplet impulses completely or almost completely into the contact tip 900 pulled back so that the board X is in a range of 0 to 0.15 inches. Such embodiments are capable of the distal end of the wire 140 to keep at the desired background heating temperature, without other sections of the wire 140 , which are not near the distal end to overheat. In other exemplary embodiments, the protrusion distance may be greater, especially if larger diameter consumables are used. For example, in some example embodiments, the protrusion distance may be in the range of 0.75 to 2 inches. Of course, in some other embodiments, a longer board may be used.

Let us turn now 10 to where another exemplary system 1000 is shown, wherein the contact tip assembly 1010 is capable of more than one wire 140 / 140 ' to the workpiece 115 supply. In some additive manufacturing operations, it may be desirable to use different wires for different manufacturing stages. The system 1000 allows switching between different wires depending on what is desired for the production. Although not shown, every wire can 140 / 140 ' be coupled with its own wire feeder to the respective wires 140 / 140 ' to advance or withdraw as needed during manufacture. That's why the control unit can 195 during manufacture, the contact tip assembly 1010 Position it so that the right wire is used for manufacturing. For example, it may be desirable to have a base with a first consumable 140 to build up that has first properties, and then to add a layer to that base, using the wire 140 ' having other properties to achieve a desired manufacturing result. For example, the wires can 140 / 140 ' depending on the desired manufacturing parameters have different sizes, shapes and / or compositions. It should also be noted that while the contact tip assembly has only two wires 140 / 140 ' however, embodiments of the present invention may also utilize a contact tip assembly or separate contact tips to provide any number of varying consumables. Embodiments of the present invention are not limited in this regard.

Furthermore, the contact tip assembly 1010 in 10 so shown that the wires 140 / 140 ' are not isolated from each other. In such an embodiment, the correct wire becomes the workpiece 115 advanced to the deposition, and thus the current from the power supply 170 directed through this wire, whereby the deposition takes place. If the wire is to be changed, the other wire is advanced while the other is retracted so that the current path now passes through the other wire. In other exemplary embodiments, the contact tip assembly may 1010 be constructed so that the wires 140 / 140 ' are electrically isolated from each other. In such embodiments, switching may occur as described with reference to FIG 7 be discussed, used. In some example embodiments, a laser beam (in 10 not shown) the energy distribution in the puddle between the wires 140 and 140 ' influence or otherwise change by scanning between the two wires.

Positioning and movement of the contact tip assembly 1010 relative to the workpiece 115 can be influenced in different ways. In particular, any known robotic or motion control system may be used without departing from the spirit or scope of the present invention. That is, the right wire 140 / 140 ' can be positioned using any known means or method, including robotic systems, and may be controlled by the control unit 195 to be controlled. For example, the contact tip assembly 1010 comprise three or more different wires and may be constructed and used similarly to the known computer numerically controlled (CNC) machining heads which are rotated and positioned to allow the use of appropriate tools. Such systems and control logic may be used in embodiments of the present invention to accomplish the desired positioning of the desired wire.

The wires (or consumables) used with embodiments of the present invention must have a size and chemical composition corresponding to the requirements of a particular manufacturing operation. In general, the wires have a circular cross section, but other embodiments are not limited thereto. Other exemplary embodiments may use non-circular cross-section wires in accordance with the manufacturing process and manufacturing process. For example, the wires may have a polygonal, oval or elliptical shape to meet desired manufacturing criteria. Wires with a circular cross-section can have a diameter in the Range from .010 to .045 inches. Of course, larger areas (for example, up to 5 mm) may be used if desired, but the control of the droplet may become more difficult as the diameter becomes larger. Thanks to the use of the laser and heating control methodologies described herein, embodiments of the present invention can enable very precise fabrication. This is especially true for embodiments that use smaller diameter wires, such as in the range of 0.010 to 0.020 inches. By using such small diameters, a large DPI (droplet per inch) ratio can be achieved, thereby enabling highly precise and detailed fabrication. The chemical composition of the wires should be selected to achieve the desired properties for the component being manufactured. Furthermore, the wire (s) used may have either a solid or a metal core configuration. Coreed wires may be used to create a composite structure. For example, a cored wire with an aluminum sheath and an alumina core may be used.

It should also be noted that most applications of the present invention do not require any inert gas because no arc is used with the processes described herein. However, in some applications it may be desirable to use a shielding gas to prevent oxidation or for other purposes.

11 shows another exemplary embodiment of the present invention. 11 shows an embodiment similar to that in FIG 1 shown. However, certain components and connections are not shown for clarity. 1 shows a system 1100 in which a heat sensor 1110 to monitor the temperature of the wire 140 is used. The heat sensor 1410 It can be of any known type used to detect the temperature of the wire 140 is capable. The sensor 1110 can make contact with the wire 140 make or can with the top 160 be coupled to detect the temperature of the wire can. In another exemplary embodiment of the present invention, the sensor is 1110 of a type that uses a laser or infrared beam capable of detecting the temperature of a small object, such as the diameter of a flux cored wire, without the wire 140 to touch. In such an embodiment, the sensor is 1110 positioned so that the temperature of the wire 140 on the board of the wire 140 can be detected; so at a point between the end of the top 160 and the sweat puddle. The sensor 1110 should also be positioned so that the sensor 1110 for the wire 140 does not feel the temperature of the sweat puddle.

The sensor 1110 is with the sensing and control unit 195 (regarding 1 discussed), so that temperature feedback information to the power supply 170 and / or the laser power supply 130 can be transmitted, so that the control of the system 1100 can be optimized. For example, the power or current output of the power supply 170 based on at least the feedback from the sensor 1110 to be adjusted. That is, in one embodiment of the present invention, either the user can set a desired temperature setting (for a particular weld and / or wire 140 ) or the sensing and control unit 195 may set a desired temperature based on other user input data (wire feed speed, electrode type, etc.) and then the sensing and control unit would 195 at least the power supply 170 control so that the desired temperature is maintained.

In such an embodiment, it is possible to heat the wire 140 to take into account, due to the laser beam 110 can come on the wire 140 impinges before the wire enters the weld puddle. In embodiments of the invention, the temperature of the wire 140 only via the power supply 170 be controlled by the current in the wire 140 is controlled. However, as discussed above, in other embodiments, at least a portion of the heating of the wire may occur 140 from the laser beam 110 come on at least part of the wire 140 incident. In that sense, the power or the power from the power supply 170 not alone for the temperature of the wire 140 be representative. Accordingly, the use of the sensor 1110 the regulation of the temperature of the wire 140 by controlling the power supply 170 and / or the laser power supply 130 support.

In a further exemplary embodiment (also in FIG 11 shown) becomes a temperature sensor 1120 instructed to sense the temperature of the weld puddle. In this embodiment, the temperature of the welding puddle also becomes the sensing and control unit 195 coupled. However, the sensor can 1120 in a further exemplary embodiment also directly with the laser power supply 130 be coupled. The feedback from the sensor 1120 is used to control the output of the laser power supply 130 or the laser 120 used. That is, the energy density of the laser beam 110 can be modified to to ensure that the desired welding puddle temperature is achieved.

In another exemplary embodiment of the invention, the sensor becomes 1120 not aimed at the puddle, but he can work on an area of the workpiece 115 be directed next to the sweat puddle. Specifically, it may be desirable to ensure that the heat input to the workpiece 115 is minimized next to the deposition site. The sensor 1120 may be positioned to monitor this temperature sensitive area so that a threshold temperature adjacent to the deposition site is not exceeded. For example, the sensor 1120 monitor the workpiece temperature and the energy density of the beam 110 decrease by the sensed temperature. Such a configuration would ensure that the heat input next to the deposition site would not exceed a desired threshold. Such an embodiment can be used in precision manufacturing operations where the heat input into the workpiece is important.

In another exemplary embodiment of the present invention, the sensing and control unit 195 coupled to a feed force detection unit (not shown) connected to the wire feed mechanism (not shown, but see Figs 150 in 1 ) is coupled. The feed force detection units are known and detect the feed force applied to the wire 140 is applied while moving to the workpiece 115 to be led. For example, such a detection unit may measure the torque generated by a wire feed motor in the wire feeder 150 is applied, and thus parameters with respect to the contact between the distal end of the wire 140 and the workpiece 115 monitor. This can be used in conjunction with current and / or voltage monitoring to stop the supply of the wire after making contact with the puddle to allow the separation of the droplet D. Of course, the control unit 195 As already noted, only use voltage and / or current sensing to determine the contact between the wire 140 and detect the puddle, and may use this information alone to stop the supply of wire if desired, once the contact has been made.

In a further exemplary embodiment, the sensor 1120 be used to detect the size of the puddle area on the workpiece. In such embodiments, the sensor 1120 may be either a thermal sensor or a visual sensor and may be used to monitor an edge of the puddle to monitor the size and / or position of the puddle. The control unit 195 then uses the detected puddle information to control the operation of the system as described above.

In the following, the control of the heating pulse current that can be used with various embodiments of the present invention will be further discussed. As noted above, when the distal end of the wire 140 in contact with the puddle or workpiece 115 stands, the voltage between the two be at or near 0 volts. However, in other exemplary embodiments of the present invention, it is possible to provide a current at such a level that a voltage level above 0 volts is obtained without generating an arc. By using higher current values it is possible to use the wire 140 high temperatures, which are closer to an electrode melting temperature, can be achieved at a faster rate. This can make the manufacturing process faster. In exemplary embodiments of the present invention monitors the power supply 170 the voltage, and when the voltage reaches or approaches a voltage at a point above 0 volts, the power supply stops 170 feeding electricity into the wire 140 to make sure that there is no arc. The threshold voltage level typically varies at least in part due to the type of wire used 140 , For example, in some exemplary embodiments of the present invention, the threshold voltage level is at or below 6 volts. In another exemplary embodiment, the threshold level is at or below 9 volts. In another exemplary embodiment, the threshold level is at or below 14 volts, and in another exemplary embodiment, the threshold level is at or below 16 volts. For example, if mild steel wires are used, the voltage threshold level is lower, while wires used to make stainless steel tolerate the higher voltage before an arc is generated. Therefore, such a system can monitor the voltage and control the heating current by comparing the voltage with a voltage set point so that when the voltage exceeds the voltage set point or when it is predicted to exceed the voltage set point, the current is turned off or reduced.

In other exemplary embodiments, a voltage level is not kept below a threshold, as above, but the voltage is maintained in an operating range. In such an embodiment, it is desirable to maintain the voltage above a minimum amount that ensures a current high enough to maintain the wire at or near its melting temperature but below a voltage level hold so that no arc is created. For example, the voltage can be maintained in a range of 1 to 16 volts. In another exemplary embodiment, the voltage is maintained in a range of 6 to 9 volts. In another example, the voltage may be maintained between 12 and 16 volts. Of course, the desired operating range can be through the wire 140 which is used for the manufacturing operation, so that an area (or a threshold) used for a work operation is selected at least in part based on the wire used or the properties of the wire used. When using such a range, the lower end of the range is set to a voltage at which the wire can be sufficiently deposited in the puddle, and the upper end of the range is set to a voltage such that generation of an arc is avoided.

As described above, the heating current is supplied by the power supply 170 switched off when the voltage exceeds a desired threshold voltage, so that no arc is formed. Therefore, in such embodiments, the current may be driven based on one or more predetermined or selected slew rates until the voltage threshold is reached, and then the current is turned off or reduced to prevent arcing.

In many of the embodiments described above, the power supply includes 170 Circuits used to monitor and maintain the voltage as described above. The construction of such circuit forms is known to the person skilled in the art. However, such circuits have conventionally been used to maintain the voltage above a certain threshold for arc welding.

As previously explained, the heating current can also be supplied by the power supply 170 monitored and / or regulated. This can alternatively be done in addition to monitoring voltage, power or a level of a voltage or current characteristic. That is, the current may be driven to a desired level or maintained at a desired level to ensure that the wire 140 at a proper temperature for proper deposition in the puddle but still maintained below an arc generation current level. For example, in such an embodiment, voltage and / or current are monitored to ensure that one or both are within a specified range or below a desired threshold. The power supply 170 then regulates the supplied current to ensure that no arc occurs, but the desired operating parameters are maintained.

In another exemplary embodiment of the present invention, the heating power (V x I) may also be provided by the power supply 170 be monitored and regulated. More specifically, in such embodiments, the voltage and current for the heating power are monitored to be maintained at a desired level or within a desired range. Therefore, the power supply not only regulates the voltage or current to the wire, but can regulate both the current and the voltage. In such embodiments, the heating power to the wire may be adjusted to an upper threshold level or operating range such that the power is maintained below either the threshold level or within the desired range (similar to what has been discussed above with respect to voltage). Again, the threshold or range settings are based on the properties of the wire and the manufacturing process being performed, and may be based-at least in part-on the selected flux-cored wire. For example, it may be determined that an optimum power setting for a 0.045 "diameter mild steel electrode is in the range of 1950 to 2050 watts. The power supply regulates the voltage and the current so that the power is controlled to this operating range. When the power threshold is set to 2000 watts, the power supply equally regulates the voltage and the current so that the power level does not exceed this threshold, but is close to it.

In other exemplary embodiments of the present invention, the power supply includes 170 Circuits that monitor the rate of change of the heating voltage (dv / dt), the heating current (di / dt) and / or the heating power (dp / dt). Such circuits are often referred to as forward circuits, and their general structure is known. In such embodiments, the rate of change of voltage, current, and / or power is monitored so that when the rate of change exceeds a certain threshold, the heating current to the wire 140 is switched off.

In other exemplary embodiments of the present invention, the change in resistance (dr / dt) is also monitored. In such an embodiment, the resistance in the wire between the contact tip and the puddle is monitored. As previously explained, the wire begins to neck as it warms up and this can lead to a tendency to form an arc, during which time the arc decreases Resistance in the wire is exponential too. When this increase is detected, the output of the power supply is turned off as described herein to ensure that no arc is generated. Embodiments control the voltage, current, or both to ensure that the resistance in the wire is maintained at a desired level.

12 shows an exemplary system 1200 , which can be used to supply the heating current to the wire 140 to lead. (It should be noted that the laser system is not shown for clarity). The system 1200 is with a power supply 1210 shown (which may be of a similar type as the one referred to as 170 in 1 is shown). The power supply 1210 may be from a known welding or heating power supply structure, such as an inverter power supply. Because the design, operation and construction of such power supplies are known, they are not discussed in detail herein. The power supply 1210 contains a user input 1220 that allows a user to enter data, including, for example, wire type, wire diameter, desired power level, desired wire temperature, or voltage and / or current level. Of course, other input parameters may be used as needed. The user interface 1220 is with a CPU or control unit 1230 which receives the user input data and uses this information to obtain the required operating setpoints or ranges for the power module 1250 to create. The power module 1250 may be of any known type or construction, including an inverter or transformer module. It is noted that some of these components, such as the user input 1220 , also in the control unit 195 can be used.

The CPU or control unit 1230 can determine the desired operating parameters in a number of different ways, including using a look-up table. In such an embodiment, the CPU or control unit uses 1230 the input data, for example, wire diameter and wire type, to determine the desired current level for the output (around the wire 140 to heat suitably) and the threshold voltage or power level (or acceptable operating range of voltage or power). The reason is that the power needed to heat the wire 140 based on the appropriate temperature at least on the input parameters. That is, an aluminum wire 140 may have a lower melting temperature than a mild steel electrode and thus requires less power or power to the wire 140 to melt. It also requires a wire 140 smaller diameter less power or power than a larger diameter wire. In addition, with increasing manufacturing speed (and correspondingly higher deposition rate), the required current or power level for melting the wire also increases.

Likewise, the input data is provided by the CPU or control unit 1230 used to determine the voltage or power thresholds and / or ranges (eg, power, current, and / or voltage) for operation such that the generation of an arc is avoided. For example, for a 0.045 inch diameter mild steel electrode, a voltage range setting may be 6 to 9 volts, with the power modulus 1250 is controlled so that the voltage between 6 and 9 volts is maintained. In such an embodiment, current, voltage and / or power are controlled to maintain a minimum of 6 volts, which ensures that the current or power is sufficiently high to properly heat the electrode, and the voltage is up or down 9 volts to ensure that no arc is generated and that a melting temperature of the wire 140 is not exceeded. Of course, other set point parameters, such as voltage, current, power, or resistance rate changes, may be changed by the CPU or controller as needed 1230 be set.

As shown, is a positive connection 1221 the power supply 1210 with the contact tip 160 of the system, and a negative terminal of the power supply is coupled to the workpiece W. That is, a heating current is passed through the positive terminal 1221 to the wire 140 passed and through the negative connection 1222 recycled. Such a configuration is well known.

A feedback sense connection wire 1223 is also connected to the power supply 1210 coupled. This feedback sense lead can monitor the voltage and the detected voltage into a voltage detection circuit 1240 feed. The voltage detection circuit 1240 transmits the detected voltage and / or the detected voltage change rate to the CPU or control unit 1230 that the operation of the module 1250 controls accordingly. For example, if the detected voltage is below a desired operating range, the CPU or controller will instruct 1230 the module 1250 to increase its output (current, voltage and / or power) until the detected voltage is within the desired operating range. Equally instructs the CPU or control unit 1230 . if the detected voltage is at or above a desired threshold, the module 1250 , the flow of current to the top 160 shut down so that no arc is generated. When the voltage falls below the desired threshold, the CPU or control unit instructs 1230 the module 1250 to supply a current or voltage, or both, to continue the manufacturing process. Of course, the CPU or control unit 1230 the module 1250 also instruct to maintain or deliver a desired level of power. Of course, a similar current detection circuit may be used and is not shown for clarity. Such detection circuits are well known.

It should be noted that the detection circuit 1240 and the CPU or control unit 1230 a similar construction and operation as the in 1 shown control unit 195 can have. In exemplary embodiments of the present invention, the sampling or detection rate is at least 10 kHz. In other exemplary embodiments, the sampling or detection rate is in the range of 100 to 200 kHz.

In each of the 1 and 11 are the laser power supply 130 , the power supply 170 and the sensing and control unit 195 shown separately for the sake of clarity. However, in embodiments of the invention, these components may also be integrated into a single system. Aspects of the present invention do not require that the components discussed individually above be maintained as separate physical entities or discrete structures.

In some exemplary embodiments described above, the system may be used in such a way that plating and droplet deposition are combined as described above. That is, during the manufacture of a workpiece, it is not always necessary to apply a high-precision method, for example, during the manufacture of a backing substrate. During this manufacturing phase, a hot wire plating process may be used. Such a process (and such systems) is described in U.S. Application No. 13 / 212,025, which is incorporated herein by reference in its entirety. More specifically, this application is fully incorporated into the present document in that it describes the systems, methods of use, control methodologies, etc., used to deposit material using a hot wire system in a plating or other type of build-up welding operation. If a more precise deposition process is then desired to produce the workpiece, the control unit changes 195 to a droplet deposition process as described above. The control unit 195 may control the systems described herein to use droplet deposition and plating deposition processes as needed to achieve the desired manufacturing result.

The embodiments described above can achieve rapid droplet deposition. For example, embodiments of the present invention can achieve droplet deposition in the range of 10 to 200 Hz. Of course, other areas may be reached depending on the parameters of the operation. In some embodiments, the droplet deposition frequency may be higher than 200 Hz depending on some of the parameters of the operation. For example, for larger diameter wires, a deposition frequency of less than 200 Hz is typically used, while smaller diameter wires, such as in the range of 0.010 to 0.020 inches, can achieve faster frequencies. Other factors that can affect droplet deposition frequency include laser power, workpiece size and shape, wire size, wire type, feed rate, etc.

13 shows another exemplary embodiment of the present invention, wherein a plurality of consumables can be deposited simultaneously. In the embodiment shown, four consumables are deposited. However, for embodiments, there are no limitations in this regard since any number can be used. In such embodiments, the construction of the workpiece can be accelerated because multiple consumables can be deposited in a single pass. As will be described below, still further advantages of such a configuration can be obtained.

As in the exemplary system 1300 are located in a contact tip assembly 1305 several contact tips 1303 . 1303 ' . 1303 '' . 1303 ''' , each a consumable 140 . 140 ' . 140 '' respectively. 140 '' lead to the produced workpiece. In the illustrated embodiment, the individual contact tips are electrically isolated from each other such that each contact tip can receive a separate current waveform to be used for deposition. For example, as in the exemplary system 1300 2, a power supply is electrically coupled to each contact tip so as to separately provide and control the current waveform for each consumable. It should be noted that the system control unit 195 in this figure is not shown. However, the system can 1300 a control unit 195 included as described hereinbefore to control the operation of each of the power supplies as well as the operation. In the embodiment shown is a power supply system 1310 the stand-alone individual power supply modules PS No. 1 to PS No. 4 ( 1311 . 1312 . 1313 and 1314 ), each of which is capable of outputting a self-sufficient current for the deposition of the consumables. Each of the streams may be similar to the exemplary waveforms described herein which have various parameters, and so on. Furthermore, each of the power supplies 1311 - 1314 be constructed and operated similar to the power supplies described in the present text in relation to the 1 to 12 were discussed. In some example embodiments, each of the power supplies 1311 - 1314 a separate power module in a single power system 1310 be housed within a single housing, for example. In other example embodiments, each of the power supplies 1311 - 1314 be a separate and stand-alone power supply that may be linked together to synchronize and otherwise control their operation.

During operation, the system can 1300 Create a workpiece on a substrate S by depositing multiple layers in a single pass. In the embodiment of 13 becomes every consumable 140 - 140 ''' in a separate layer L No. 1, L No. 2, L No. 3, L No. 4, each trailing consumable producing a layer on the previous layer. This is done by removing the tips 1303 - 1303 ''' arranged in a row to each other in the feed direction, as shown. During the deposition becomes the anticipatory consumable 140 deposited on the substrate S, thereby forming the first layer L No. 1, and the trailing consumable 140 ' is deposited on the previous layer L No. 1 to produce a second layer L No. 2, and so on. To allow the layers to be formed at different heights, the contact tip assembly can 1305 position the contact tips at different heights relative to the surface of the substrate S. As in 13 As shown, the contact tips have a staggered or stepped formation to allow stacking of the layers. In other exemplary embodiments, the contact tips may be at the same height relative to the surface, but the protruding distance of the consumables may be adjusted appropriately to achieve the desired stacking of layers.

In exemplary embodiments of the present invention, the spacing between the consumables (in the advancing direction) is such that the subsequent layers can be formed correctly on the previously deposited layer. In exemplary embodiments, the spacing is such that the consumables are not deposited in the same puddle. That is, the lagging consumable does not contact the previous puddle. However, the respective puddles are juxtaposed on the workpiece. That is, in exemplary embodiments, the puddles are adjacent or close to each other, but their molten portions do not contact each other. Of course, the puddles can be at different heights (see for example 13 ), and the temperature of deposition between the puddles can be very high, but the molten portions do not touch each other.

It should be noted that - although in 13 not shown - the system 1300 may also use a laser or heat delivery system as described in the exemplary embodiments described above. More precisely, the system can 1300 use a laser to create a molten puddle and / or assist in consumable melting. In some example embodiments, individual jets may be directed to each separate consumable deposition process and may be individually controlled for each respective deposition process. The individual beams may be generated by separate laser emission devices or may come from a single laser emission device, but are split into separate beams via optics and laser splitters, etc. The deposition of each consumable 140 to 140 ''' can be controlled as described above. Alternatively, in other exemplary embodiments, a single laser / heat source may be used, which is scanned between consumables during the deposition process to provide the desired heat input for each consumable deposition process. For example, a laser beam may be used to separate each consumable 140 - 140 ''' is scanned, and the interaction time at each consumable position is controlled to achieve the desired heat input for each deposition operation.

In exemplary embodiments of the present invention, the type, size and composition of the consumables 140 - 140 ''' chosen on the basis of the desired properties of the workpiece. In some embodiments, all are consumables 140 - 140 ''' the same and have the same diameter and the same composition. However, in other exemplary embodiments, the consumables may also have different properties. For example, the consumables 140 - 140 ''' have different diameters, such that the layers L No. 1 to L No. 4 are made with different widths by using consumables of varying diameter. In addition, the consumables may have various compositions that allow the production of a workpiece having varying physical and compositional properties at different locations. In such embodiments, the composition of a manufactured workpiece can be changed dynamically. That is, a first material may be used to form certain portions of a workpiece - using contact points - and then, without stopping, the system may deposit other or additional materials as needed.

For example, exemplary embodiments of the present invention may be used to make a structure or workpiece using a blend of stainless steel and mild steel. Furthermore, such structures can be formed with an added nickel material. Of course, this is just exemplary, and embodiments of the present invention allow a mixture of multiple materials to build a desired structure. In other exemplary embodiments, a strip or layer of non-magnetic material or metal, including for measuring the workpiece, may be added to the workpiece for various reasons. Mutually different materials may also be used to convert a material into an austenitic stainless steel.

In addition to varying properties or types of consumables, embodiments of the present invention may include consumables 140 - 140 ''' feed at varying wire feed rates. That is, in some embodiments, the wire feed rate is the same for all consumables. However, in other embodiments, it may be desirable to vary the wire feed rates. This can be done through the control unit 195 and the respective wire feed systems of consumables (not shown for clarity). By varying the respective wire feed rates, the physical properties of the workpiece produced can be influenced. For example, it may be desirable for at least one of the layers L No. 1 to L No. 4 to be thinner than the others. In such embodiments, the wire feed rate for the respective consumable of the thinner layer may be slowed, resulting in a thinner layer.

In addition, in exemplary embodiments, various current waveforms may be applied to the consumables 140 - 140 ''' be created. In the system shown 1300 There are separate power supply modules 1311 - 1314 which apply the respective deposition currents to the consumables. In some embodiments, all of these currents may be the same, while in other embodiments the current waveforms may be different - at different frequencies, peak current levels, etc. This may be the case if different wire feed rates and / or different consumables are used to ensure proper deposition ,

By varying aspects of the deposition of each of the consumables 140 - 140 ''' offers the system 1300 4, that is, in exemplary embodiments, each or a combination of consumable type, composition, diameter, wire feed rate, and deposition current waveform may be varied relative to another consumable. to achieve a desired property of a layer or deposition process. Thus, embodiments of the present invention allow the rapid construction of a workpiece with a high degree of flexibility and precision in building each layer or depositing a consumable. That is, different layers may have different thicknesses, widths, shapes, etc., based on the use of varying deposition and consumable properties.

14 shows another view of the in 13 shown system 1300 , As shown and discussed above, the contact tips are 1303 and 1303 ' at the contact tip assembly 1305 mounted, which aligns the contact tips as needed, holds and moves. Furthermore, as discussed above, the contact tips are held in a staggered or stepped formation to allow the formation of the layers one above the other, as shown. In such embodiments, board X remains for each of the respective consumables 140 . 140 ' generally considered the same distance. However, this need not be the case in other embodiments. That is, the protruding distance X for each respective consumable 140 . 140 ' can be varied to achieve a desired deposition performance. In some Embodiments may be the contact tips 1303 . 1303 ' also be fixed so that their respective distal end surfaces relative to the surface of the substrate S are coplanar with each other. In such an arrangement, the protruding distance X of trailing consumables (for example 140 ' ) lower than any previous consumable (for example 140 ) when the layers L No. 1, No. 1 are formed as shown.

Furthermore, as shown, in some embodiments, the contact tips are 1303 . 1303 ' inside the contact tip assembly 1305 movable. In such embodiments, an actuator mechanism 1320 , such as rollers, an actuator, etc., used to contact the tips 1303 . 1303 ' into and out of the contact tip assembly 1305 to move to provide the desired board and / or the desired geometry of the formed workpiece. The actuators 1320 can through the control unit 195 (in 14 not shown) can also be controlled such that the contact tips can be moved dynamically during a deposition process. For example, during deposition, the relative height of the contact tips and / or the protrusion distance X of the consumables may be adjusted to achieve the desired geometry of the manufactured workpiece. This movement can be accomplished in various ways, as described above. For example, servos, motor control rollers, linear actuators, etc. may be used to move the contact tips as needed. Such control improves the flexibility of the production capabilities of the system 1300 ,

It should be noted that the 13 and 14 Although the contact tip assembly 1305 such that the consumables lie in line in a feed or deposition direction but that the contact tip assembly 1305 can also be positioned in a lateral configuration, wherein the contact tips are in a line that is normal to the feed direction. That is, the contact tips may be juxtaposed to provide a wide material deposit. In such an embodiment, the consumables are deposited side by side rather than over each other, as in FIGS 13 and 14 shown. Of course, in other exemplary embodiments, the contact tip assembly may 1305 be aligned such that the contact tips are oriented at an angle relative to the feed direction. Embodiments of the present invention are not limited in this regard.

15 shows another exemplary embodiment, wherein the contact tip assembly 1305 is also rotatable relative to the feed direction of the deposition process. As shown in this plan view, the consumables are deposited in a line in a first position A, as in the 13 and 14 shown. As the contact tip assembly degrades 1305 it advances, it is rotated to a new position B, such that the shape of the deposition of the layers changes, as shown. The contact tip assembly 1305 can be controlled and rotated by any known components and methods, such as using a stepping motor, motor, or other known system (for example, those systems used in robotic welding to control motion and rotation ). The control unit 195 can be used to control the rotation or movement of the contact tip assembly 1305 be used relative to the substrate S. By looking at the assembly 1305 rotatable, a shape of the workpiece can be obtained as needed. For example, a wall thickness of a workpiece may be increased or decreased as needed. Furthermore, during the rotation of the assembly 1305 each or a combination of wire feed speed, current waveform, board and / or contact tip position are adjusted for each of the consumables. For example, as in 15 only one of the consumables is deposited in front of position A to produce layer L # 1, as shown. This can be the anticipatory consumable in the assembly. While the assembly 1305 is rotated, the deposition of a second consumable begins 140 ' for a second layer L No. 2, such that the deposit L No. 2 is coupled to and deposited on the first layer L No. 1. This can be done without the addition of an undesirable height, but only to widen the workpiece produced. Similarly, the deposition of subsequent consumables 140 '' and 140 ''' similarly and sequentially begin while the assembly 1305 is rotated to the desired position B. Likewise, this movement can be used to create a ledge or overhang on the workpiece without the need to additionally support the overhang. In such embodiments, the rotation of the assembly 1305 and adjusting the deposition of any or all of the consumables (as described above) will allow the overhang to be made relatively easily. For example, adjusting the feed rate and / or the board or contact tip depth positioning may allow the generation of a paragraph in a relatively simple manner.

That's why the system increases 1300 to a great extent the manufacturing flexibility of the present Text described additive manufacturing processes and systems.

The 16 . 17A -C and 18A show exemplary embodiments of a substrate 1600 which can be used with the methods and systems described herein. The substrate 1600 is electrically conductive to provide a current path for the deposition current or deposition waveform, but also has a non-bonding surface 1610 such that it is relatively easy to remove a workpiece from the substrate after completion of the manufacturing process 1600 take down.

Typically, in additive manufacturing, the workpiece to be manufactured is placed on a substrate or surface that is conductive to form a proper current path for the consumable heating current. However, because the substrate is conductive (i.e., metallic), the workpiece is bonded to the substrate. That is, during the start of production of the workpiece, the initially formed layers are adhered to the substrate by the deposition process. Because of this, an additional processing step is needed to take down the workpiece from the substrate, and eventually remove a portion of the substrate material from the finished workpiece. This adds additional processing steps and creates a potential risk of damage to the workpiece. It will be appreciated by those of ordinary skill in the art that bonding between a workpiece and the substrate generally occurs when a fusion occurs between the workpiece and the substrate, such that the material from the workpiece contacts the material of the substrate in a mixing zone on the substrate mixed according to connection technologies. Embodiments of the present invention solve this problem.

16 shows an exemplary substrate 1600 which is made of a conductive material that allows current to flow therethrough, but prevents the workpiece 110 Bonded to it. For example, in some example embodiments, the substrate may be made of copper or graphite that is conductive but does not bond to aluminum or steel workpieces. In other exemplary embodiments, the substrate 1600 as a matrix of a number of different materials. For example, the substrate 1600 be made of a non-electrically conductive ceramic or clay matrix material, wherein a conductive (for example, metallic) material is distributed within the ceramic or clay matrix, so that a conductive path is formed. As in 16 are shown in the non-conductive matrix 1603 conductive particles 1605 distributed, leaving a current path from the surface 1610 up to a grounding point 1625 can be formed, to which a connection wire of a power supply can be connected. In some example embodiments, the substrate may be 1600 predominantly made of ceramic, in the copper particles 1605 are distributed and which are provided with a sufficient amount of copper to form a copper density, which allows to flow an electric current from the workpiece surface of the substrate to another location of the substrate, to which a ground or power cable is attached. The conductive material 1605 , which may be copper, may be in either powder, grain, filament or ribbon form. However, the conductive material should be distributed so as to provide an electrically conductive path from the surface 1600 to the grounding point 125 is formed. The grounding point 125 can be anywhere on the substrate 1600 be positioned. It should be noted that in some example embodiments, it is not necessary for the conductive material to be uniform throughout the substrate structure 1600 but it should be sufficiently even in the workpiece surface 1610 be distributed to form a current path from the point where a workpiece on the substrate surface 1610 is positioned or begins. The matrix material 1603 can be any material or combination of materials that does not bond to the workpiece. The materials may be non-conductive and have a high melting temperature, leaving the surface of the matrix 1603 does not melt during the process of forming the workpiece on the surface. As indicated above, the matrix material may be clay, ceramic or a combination thereof. Other materials may include cast iron that has a high carbon content or any other alloy that would become brittle when the additive process is performed on the surface. As described above, the additive process has relatively little (if any) mixing so that spreading of the alloy from the substrate into the assembly is minimal. However, the spreading may be such that the first layer of the structure becomes brittle while at the same time still being conductive. If the assembly is complete, then the user can then easily bend and break the brittle interface to separate the assembly from the substrate. As indicated above, a ceramic material may be used for the substrate. Such ceramic materials should have a high melting temperature, such as Al ₂ O ₃ , or other similar ceramic materials. In another example, an aluminum material or alloy may be used as a substrate for mild steel construction.

In a further exemplary embodiment, the substrate may be metallic Powder having a density such that the substrate provides the desired conductivity and physical support force for the build-up workpiece. In such embodiments, the powder can be easily tapped off the build after completion. In other exemplary embodiments, the substrate may be a conductive layer (eg, copper, carbon, iron, etc.) placed on a base of non-conductive material, such as ceramic, with conductive materials within the base material but do not have to. By using a thin layer on a base material, penetration into the substrate can be minimized, ensuring that there is no bonding to the substrate.

As in 16 In some example embodiments, the substrate may be shown 1600 a contact zone 1620 have in which the conductive material is present and outside of which no conductive material is present or is present only to a lesser extent, so that the substrate 1600 outside the contact zone 1620 less conductive or non-conductive. In such embodiments, the workpiece becomes 110 on the surface 1610 Started or placed in such a way that it is the contact zone 1620 touched to ensure sufficient electrical contact, since outside the contact zone 1620 little or no electrical conductivity exists. In such embodiments, the contact zone 1620 an area smaller than the surface 1610 , Furthermore, the contact zone 1620 have any desired shape. Thus, to begin an additive manufacturing process in exemplary embodiments, the process begins in the contact zone 1620 the surface 1610 to ensure that a path for the workpiece exists. While the workpiece 110 can be formed, sections of the workpiece on the surface 1610 outside the contact zone 1620 can be formed as long as the workpiece is made as an integral piece and so has a constant current path. Thus, a current path is always provided for the manufacturing process, and the workpiece 110 can on a conductive surface 1610 are made, which are not attached to the workpiece 110 Bonded, which allows easy removal and machining of the workpiece.

17A shows another exemplary embodiment wherein the substrate 1600 a grid 1630 Made of conductive material, creating a grid structure on the surface 1610 of the substrate 100 arises. The grid 1630 is made of a conductive material, such as copper, and is in the material of the substrate 1600 embedded, which may be ceramic, clay or other non-conductive material. The grid 1630 can be formed so that a lattice structure on the surface 1610 is formed such that regardless of the size or orientation of the workpiece to be formed 110 the workpiece at least part of the grid 1630 touched to form the required conductive path. The grid 1630 should have such a mesh size that the desired spacing is formed for the size of the workpieces placed on the substrate 1600 are to produce. In some embodiments, the grid may be 1630 have a depth through the substrate 1600 ranges, while in other embodiments, the depth of the grid 1630 not through the entire substrate 1600 enough. Furthermore, the grid structure becomes 1630 formed so that the structure is continuously conductive, allowing it regardless of where a workpiece makes contact with the lattice structure 1630 establishes an electrical path to the grounding point 1625 gives. Furthermore, in exemplary embodiments, the grid structure needs 1630 in the substrate 1600 only to be present in a contact zone similar to that with respect to 16 is described. That is, the lattice structure leading to the surface 1610 is exposed only in a discrete area of the surface 1610 (ie the contact zone), and the grid is at the grounding point 1625 coupled. In such embodiments, a current path exists to allow the fabrication of the workpiece as long as any portion of the workpiece is in the contact zone and makes contact with a portion of the grid 1630 manufactures. Because, however, most of the surface 1610 non-conductive and non-bonding, the removal and processing of the workpiece is also easy in comparison to known substrates.

17B shows another exemplary embodiment of a substrate 1600 which can be used with devices described herein. In this embodiment, the substrate comprises 1600 several discrete grounding points 1651 / 1652 / 1653 etc., over an area of the substrate 1600 are distributed. The points may be distributed in a structure, such as a grid structure, such that their respective locations are known to the controller of each system using the substrate. The grounding points are made of a conductive material and can be wires, pins, etc., and can thus pass through the substrate 1600 They also run on a different surface of the substrate 1600 are exposed. In the in 17B In the embodiment shown, the earthing points run through the substrate in this way 1600 that its other ends on the bottom of the substrate 1600 are exposed. In other embodiments, if desired, the other ends may exit on a side surface. Each of the grounding points 1651 . 1652 . 1653 etc. is electrical with a logic circuit 1660 coupled, which also electrically with the Power system and coupled to the control unit, which controls the operation of grounding switches within the circuit 1660 controls as described below. Because the locations of the grounding points are known, an additive process may be at a grounding point (for example, point 1651 ), which serves as the initial grounding path for the additive process. Once the process is started, the puddle can move along the surface 1610 be moved until the next grounding point 1652 reached. The logic circuit 1660 may allow the control unit to switch the grounding point of the build process to the nearest ground point for the ongoing additive process. That is, when the contact tip of the process is moved, the ground point may be toggled to provide the nearest ground path for the operation. Furthermore, in other exemplary embodiments, the logic circuit 1660 open more than one grounding path - through multiple grounding points - to increase the amount of current that can be used for the process. Furthermore, in exemplary embodiments, the logic circuitry 1660 be used to direct the grounding current path to different locations to control the deposition process. For example, if the build process is at one edge of the substrate 1600 approaching, so can the switch 1660 switch to ground points that are closer to the center of the substrate 1660 to help control the deposition process and the puddle. This may also be used to assist in controlling the direction of an arc insofar as an arc is initiated in the deposition process.

17C shows another exemplary embodiment of the present invention wherein the substrate 1600 furthermore a ladder 1670 contains, the electrically all grounding points 1651 . 1652 . 1653 etc., and the ladder 1670 is coupled to the power supply to complete the grounding path for the deposition current. In such embodiments, no linking circuit is needed 1660 as described above. In the embodiment shown, the conductor 1670 a conductive plate or layer attached to a surface of the substrate 1600 is mounted, to which all grounding points are coupled. Of course, the ladder needs 1670 not to be located at the bottom, but may also be on another surface of the substrate 1600 are located. During use, since the body structure more than a grounding point 1651 etc., additional grounding paths for the conductor 1670 which also allows more power to be used in the process. In any of the embodiments described above, the control unit or power supply used for the deposition process may control the deposition current level so that an acceptable current level for each individual grounding point is not exceeded. That is, at the beginning of a building process, if only a single grounding point 1651 is used, the current is controlled so that the current level becomes an acceptable level for a single ground point 1651 does not exceed. Otherwise the grounding point could be damaged. However, as the design progresses to additional grounding points, the controller may cause the current level to increase due to the additional grounding points contacted, because of an increased number of grounding paths to the conductor 1670 available. Therefore, in such embodiments, because the control unit knows the location of each of the grounding points, the control unit can then increase the current as more and more grounding points are used. In such embodiments, the deposition current may be increased incrementally with the contact of each respective grounding point, or may be increased in a single step when a suitable number of grounding points are touched. For example, for a deposition current of 200 A (using stored information), the control unit may determine that at least 4 grounding points are needed for such a current level. The controller or power supply may use a first, lower, current level (eg, 50A) until at least 4 grounding points have been contacted, at which time the deposition current is increased to the optimum level. In other embodiments, the current may be increased in increments when a new ground point is touched each time until the minimum number of ground points required has been contacted. For example, the current may be increased by 50A for each subsequent grounding point until the desired deposition current level is achieved. The power increase steps may be pre-entered or preprogrammed into the system controller.

In exemplary embodiments of the present invention, the grounding points are wires or pins having an average diameter greater than the wire diameter used. In exemplary embodiments, the grounding points are pins having an average diameter of at least 20% over the largest wire diameter used. In some exemplary embodiments, the diameter is in the range of 20 to 80% above the diameter of the largest wire diameter. Furthermore, as in 17C As shown, the pins have a larger top surface as shown to provide additional contact with a workpiece. That means the pins can be a larger one Head face (for example like a nail, etc.) on the contact surface of the substrate have (see for example 17C ). Insofar the pins 1651 etc. a shape as in 17C As shown above, the larger head area is not taken into account in determining the average diameter of the stylus as discussed above.

In further exemplary embodiments, the grounding points 1651 etc. (for example, pins, wires, rods, etc.) within the substrate 1600 taken out and replaced. For example, as in 17C As shown, the pins simply rest in holes in the substrate and act as the earthing points described above. By blending, the pins are attached to the workpiece as it is being assembled, and then the workpiece is removed upon completion, along with the attached pins. Then the pins, rods, etc., can be removed by a machining process, and new pins can instead be inserted into the substrate 1600 be used for the next process. The removable pins 1651 etc. should be of sufficient length to make contact with a workpiece on the substrate and contact plate 1670 is constructed so that a proper grounding current path can be established.

18A shows another exemplary embodiment of the present invention wherein the substrate 1600 at least one cooling channel 1640 contains, through which during the production of a workpiece or at least during the start of the production of a workpiece, a cooling medium can be passed. The cooling medium may be a gas or a liquid and is used to maintain the substrate at a temperature such that no portion of the surface 1610 melts or otherwise adheres to a workpiece. By cooling the substrate 1600 by using a cooling manifold or channel 1640 can the surface 1610 kept cool, and all electrically conductive materials on the surface 1610 (For example, lattice structure, conductive particles, etc.) can be kept cool, leaving no layer of the workpiece on the surface 1610 is formed, melts or otherwise bonding with the electrically conductive components on the surface 1610 received. Other embodiments may use other cooling methods or processes without departing from the scope or spirit of the present invention. For example, passive heat pipes can be used.

Thus, in exemplary embodiments, a substrate is provided that has the required electrical conductivity but also provides a nonbonding surface such that removal and machining of the workpiece after fabrication is easier.

18B shows another structure that can be used with the example additive manufacturing processes described herein. The additive manufacturing processes described herein can be used to make complex and fragile workpieces. Simple production of components such as these can be assisted by starting the manufacturing process from a non-horizontal, conventional substrate or non-horizontal, conventional desktop. For example, it may be advantageous to make the workpiece in a hanging configuration. That is, it may be easier to manufacture the workpiece when the initial layers or the initial deposition of the workpiece layers are suspended, such that they extend from a bottom surface of a substrate - as opposed to a conventional bottom-up facing substrate with a flat surface. In the 18B shown embodiment shows an exemplary stiffening structure 1800 that can be used in these situations. The stiffening structure 1800 can have several support components 1810 and 1820 that are electrically coupled together for current to flow. The stiffening structure 1800 is configured to hold a workpiece at any point on the structure 1800 can be started as needed for each given workpiece. For example, if it is easier to make a top-down or top-down workpiece, the part may be at a point on one of the elements 1810 and 820 started and built down using the processes described in the present text. Of course, the stiffening structure and burner used, or the contact tips used, should be sized so that the tips fit properly in the stiffening structure 1800 can be positioned. The part can then as needed by the structure 1810 / 1820 from down to the surface of a substrate 1600 being constructed. As shown, the stiffening structure 1800 their own ground contact point 1825 have or may simply be electrically conductive throughout. Furthermore, in some example embodiments, the stiffening structure may be contact protrusions 1830 have at which the beginning of a part or workpiece is fixed to start a building operation. These projections 1830 act as contact nodes at which the beginning of a workpiece is started. These projections may make it easier to start a manufacturing process and may make it easier to separate the finished part from the stiffening structure without damaging the manufactured part. The projections 1830 can be integral with the parts 1810 / 1820 the structure 1800 getting produced. In other embodiments, the protrusions 1830 be made of a different material and / or be easily removable from the structure. For example, the projections 1830 Be pins or other fastener-like components having a head or projection portion to which a part can be attached and started for a manufacturing process. Upon completion, the pins can be removed from the stiffening structure so that the manufactured part can be easily removed. The stiffening structure 1800 can take any desired shape or configuration for a given manufacturing process.

In exemplary embodiments, the stiffening structure 1800 a metallic structure, which is the transfer of the current to the substrate 1600 which may be any of the embodiments described above. In other exemplary embodiments, the stiffening structure may be made of a non-bonding but conductive material, as generally discussed above with reference to FIGS 16 and 17 is described. In any case, the structure should 1800 be constructed to form a current path either to the substrate 1600 or a grounding point 1825 can provide to allow the proper flow of the heating current.

19A . 19B and 19C show exemplary embodiments of a consumable 1900 for additive manufacturing, which can be used with embodiments of the invention described herein. It is generally understood that massive, large diameter consumables require more power or energy to melt the consumable. However, smaller diameter consumables require less power or energy for melting, such that less power or energy is needed to melt multiple smaller diameter consumables, which together have the same cross sectional area as a single larger diameter solid wire. Therefore, the consumable used in some exemplary embodiments of the present invention is a braided consumable 1900 that made of several wires 1903 exists, which are braided. In some embodiments, the wires are 1903 the same and have the same diameter and the same composition. However, the wires can 1903 be different from each other in other exemplary embodiments. For example, in some embodiments, two different types of wires may be used to form the braided consumable 1900 manufacture. In such an embodiment, the wires may be different based on the diameter and / or the composition. For example, the middle wire may have a first diameter and a first composition, and the peripheral wires 1903 have a second diameter and a second composition that are both different than the first diameter and the first composition. This allows the use of a consumable 1900 which has specially adapted properties for a particular manufacturing process. It should be noted that the methods and systems for depositing solid or core-containing consumables described herein can also be used to deposit a braided consumable such as that disclosed in U.S. Pat 19A is shown.

Furthermore, in the in 19A shown embodiment of the middle wire 1903 ' a non-braided wire, and the outer circumference of wires 1903 is around the middle wire 1903 ' braided. The braid may be in a generally helical structure along the length of the consumable 1900 getting produced.

In some example embodiments, the mesh of the consumable 1900 to increase the relative wire feed rate of a consumable type. Like in 19A shown, the middle consumable 1903 made of a first type or material, and the surrounding wires 1903 can be made of a different type or material. Because the length of the surrounding (outer wires) is longer than that of the middle wire, for a given length of consumable material 1900 the effective deposition rates of each of the respective wire types are different. The effective relative rate of deposition of different wire types can also be affected by the relative number of wire types in a given bundle. Thus, embodiments of the present invention allow for increased flexibility in the chemical composition of the deposit.

19B and 19C show another exemplary embodiment of a consumable that may be used with embodiments of the present invention. However, unlike the consumables 1900 in 19A the consumables 1900 in the 19B and 19C a white space 1910 at the core of the consumable, where the core 1910 through several braided wires 1903 is surrounded. This hollow consumables construction allows the consumables 1900 during the deposition to squeeze and "shape", so that the Abscheidungsprozess can be adjusted. This will be explained in more detail below.

The network of wires 1903 that the outside of the consumable 1900 form takes place in a general helical pattern, similar to the known wire braiding techniques, but a void 1910 remains at the core of the consumable 1900 maintained. As in 19A , the wires can 1903 in some embodiments have the same diameter and the same composition while the wires 1903 in other embodiments may have other properties. An example of this is in 19C shown where the braid is a first type of wire 1903 with a first diameter and a first composition and a second wire type 1905 containing a second diameter and a second composition. Of course, in some embodiments, the diameters of the wires 1903 / 1905 be different while the compositions may be the same. As in 19C shown, the different wires alternate 1903 / 1905 around the peripheral edge of the cross-section of the consumable 1900 around. In other exemplary embodiments, the wires 1903 / 1905 have different melting temperatures, which may allow customized deposition profiles and laminations as needed.

The white space 1910 should be such that the consumables 1900 ' remains relatively stable in the deposition process. If the void is too large, the consumable may become unstable and will not retain its integrity in the deposition process. In exemplary embodiments, the diameter of the void is 1910 in the range of 5 to 40% of the effective diameter of the consumable 1900 ' , The "diameter of the void" 1910 is the diameter of the largest circular cross section that is in the void 1910 can be accommodated, as in 19C shown as a dashed circle. The "effective diameter" of the consumable 1900 ' is the diameter of a circle with the same cross-sectional area of the combined cross-sectional area of all the wires 1903 / 1905 that make up the consumables 1900 ' consists.

As indicated above, the consumable material 1900 with a central white space 1910 during the deposition process to allow a change in the deposition characteristics of the consumable. This is common in the 20A and 20B shown where the consumables 1900 was squeezed in a direction relative to the feed direction of the consumable to achieve the desired width of the deposit. As described herein, processes and systems of the present invention can be used to fabricate complex shapes by additive manufacturing. Thus, workpiece and molds having varying thicknesses, etc. can be produced. That in the 19B and 19C shown consumables 1900 Thanks to the white space, these complex shapes and different thicknesses can be easily produced. In 20A The consumables are squeezed in a direction normal to the feed direction, which is the consumable 1900 makes narrow relative to the feed direction. As a result, the resulting deposit becomes narrower than the original diameter of the consumable. Equally shows 20B the same consumables 1900 which is squeezed in a direction along the feed direction, resulting in a broadening of the consumable 1900 relative to the feed direction leads. Therefore, with such squeezing, a wider deposition can be made as needed. As described above, the white space should be 1910 have a size or a diameter that the deformation of the consumable material 1900 allowed to change its relative width compared to its uncompressed state.

In some example embodiments, the void may be 1910 be filled with a flux or powder of a desired chemical composition, which is needed for the deposition. This may assist in delivering a desired material to the structure that does not readily wire or transfer by the melting of the wire. For example, an abrasion-resistant powder may be added as a flux.

20C shows another exemplary embodiment of a contact tip assembly 2000 and a consumable supply system and method that can be used with embodiments of the present invention. In this embodiment, at least two consumables 2010 and 2020 to the contact tip assembly 2000 and the contact tip 2040 passed an estuary 2030 which allows both consumables to be passed through. In contrast to the embodiments described above, the consumables 2010 and 2020 not braided. They can come from the same source of consumables (reel, reel, etc.) or can be supplied from separate sources. Furthermore, they may be the same consumable having the same dimensions and composition, or they may be different as needed for a given manufacturing operation. In other exemplary embodiments, the consumables 2010 and 2020 be supplied at different rates, and in In some embodiments, the feed rates may be changed dynamically during a deposition process. Such embodiments allow for the special adaptation of alloys for construction during the deposition process. For example, during a first portion of the process, the consumables become 2010 and 2020 supplied at the same rate, but at various stages of the building process becomes the consumable 2010 slows or accelerates as needed to produce the desired chemical composition of the deposit.

Furthermore, while two consumables are shown, other embodiments may use three or more as needed. In the embodiment shown, the consumables 2010 and 2020 to the mouth 2030 (which may be of oval shape or any other shape to accommodate the consumables) and are then fed to the workpiece by known consumable supply systems. During deposition, the contact tip becomes 2040 oriented so that the consumables provide the desired deposition profile. Furthermore, the contact tip 2040 rotatable (as in the embodiments described above), so that the consumables can be aligned according to the specifications and the shape or the profile of the deposition process can be changed as needed. For example, as shown, the left alignment indicates alignment in a line, resulting in a narrow deposition on the workpiece, but with a greater height, since the consumables lie in line in the feed direction. Then the contact tip 2040 be rotated as needed to the position shown on the right. The rotation can be through the control unit 195 and motors, etc. and can be used during changes in the direction of deposition without having to change the orientation of the burner. The positioning on the right side can be used if it is desired to increase the width of the deposition in the feed direction. It should also be noted that in some embodiments it may not be necessary to use both consumables 2010 and 2020 feed simultaneously. In such embodiments, the consumables would 2010 and 2020 supplied by separate wire feeders (not shown) and the control unit 195 can control which of the consumables is supplied or whether they are supplied simultaneously. In such embodiments, the un-guided consumable does not need to exit the mouth 2030 can be withdrawn and thus can be used to maintain the positioning of the currently supplied consumable. In such embodiments, the supply of consumables by the control unit 195 which supplies either one or both of the consumables as needed at a given moment during the process.

Furthermore, uses in the in 20C shown embodiment of each of the consumables 2010 and 2020 the same stream, as they pass through a single muzzle 2030 be guided. In such embodiments, the power may come from a single power source, and the power is shared by both consumables. However, shows 20D another exemplary embodiment. In the in 20D The illustrated embodiment includes the contact tip assembly 2000 two electrically isolatable contact tip sections 2015 and 2025 , The top sections 2015 and 2025 lead the consumables 2010 respectively. 2020 to. However, the assembly contains 2000 a switching device or a switching mechanism 2050 , the or the top sections 2015 and 2025 electrically coupled together, such that they share a current, or electrically isolate the tip portions of each other. In an exemplary embodiment, each of the tip sections 2015 and 2025 with a separate power supply (PS No. 1 and PS No. 2) coupled. When the switch 2050 is in an open position, then each respective power supply can feed a separate and independent heating current into the respective consumables. In such embodiments, the consumables may be deposited at different rates and / or may vary in size and composition. This can be controlled and used using multiple consumables as in similar embodiments described above. However, in this embodiment, the control unit 195 close the switch as needed; at this moment, the contact tip sections become 2015 and 2025 electrically coupled and can use a single current signal from one of the power supplies PS No. 1 or PS No. 2. In such embodiments, it only needs to be required to operate a single power supply for a particular operation in order to reduce power consumption and / or eliminate the need to synchronize signals. In such embodiments, the switch 2050 closed, so now each of the top sections 2015 and 2025 can be coupled with the other, so that the consumables 2010 and 2020 share the same signal from a single source. When the switch 2050 is opened, the tip portions are electrically isolated from each other (via a dielectric material or other convenient means), and if both consumables are to be deposited, they would receive separate signals from separate power supplies. Alternatively, at some point during a deposition operation, it merely needs to be required to deposit a single consumable. Thus, only a single power supply is operated, but the switch 2050 opens to isolate the other consumables for safety reasons. The switching mechanism 2050 can be any switch structure that is capable of the tip sections 2015 and 2025 to insulate and connect, and can be placed in the tip assembly as needed 2000 integrated or from the assembly 2000 be spatially separated.

We turn now to the 21A and 21B to where is a diagrammatic view of a representative contact tip assembly 1950 shown is the consumable 1900 from 19B used. The 21A and 21B show a view at the exit portion of the contact tip assembly 1950 looks upwards, being 21A shows the consumable in a non-compressed state and 21B the consumables 1900 in a compressed state. It should be noted that the following description of the contact tip assembly 1950 by way of example, and that those skilled in the art will appreciate that other configurations and designs may be used to provide the consumable 1900 mold as needed to achieve the desired deposition during an additive manufacturing process.

As shown, the contact tip assembly has 1950 a consumable opening 1951 through which consumables pass. Although the opening 1951 As a square, embodiments of the present invention are not limited in this respect, and other shapes may be used as long as the consumable material 1900 in both its compressed and uncompressed state. In the embodiment shown, the assembly has 1950 two pairs of contact plungers 1953 and 1955 , The plungers are, as shown, relative to the opening 1951 movable, such that they can extend into the opening and so a compressive force on the consumables 1900 exercise. The contact plunger 1953 and 1955 are aligned so that a pair of plungers 1953 in one direction normal to the direction of movement of the other set of plungers 1955 is mobile. Thus, as in 21B shown the pestles 1953 / 1955 the consumables 1900 squeeze in a desired direction to obtain the desired shape. Each set of plungers can by known actuators 1956 , such as linear actuators, etc., can be moved and controlled by the control unit 195 (not shown in these figures). Furthermore, each of these rams 1953 / 1955 configured to apply the heating current waveform to the consumable 1900 in such a way that the heating current is consumable 1900 is fed via the plunger. It should be noted that although a single actuator 1956 and a single bias 1957 are shown in the figures, but exemplary embodiments would have similar components for each of the plungers.

As in 21A shown during a non-compressed state, each of these plungers 1953 / 1955 a contact with the consumables 1900 to supply the heating current. The pestles 1953 / 1955 be in a position relative to the opening 1951 kept to ensure that consumables 1900 kept in its natural state. Then, during the deposition, it is determined (for example, by the controller) that a width of the consumable should be changed to achieve a desired deposition configuration: Either the consumable should be made wider or narrower as needed. On the basis of this information, the control unit initiates 195 an actuation of the plunger 1955 (via actuators 1956 ) and their inward movement to the consumables 1900 to compress, as in 21B shown. In addition, to change the shape of the consumable 1900 to pick up the pestles 1953 withdrawn so that the shape of the consumable can change. However, in exemplary embodiments, the recessed plungers have 1953 still in contact with the consumables 1900 to the consumables 1900 to hold in the correct position and to supply the heating current.

During the deposition process, the shape of the consumable 1900 be changed dynamically by moving the plungers to achieve the desired shape. For example, the control unit 195 the pestles 1953 / 1955 cause it to retreat as needed during deposition and extend to the shape of the consumable 1900 to change from a wide deposit to a narrow deposit and back again without stopping the deposition process.

As mentioned above, the movement or actuation of the plunger 1953 / 1955 be performed by any known actuators or moving devices to bring about the desired movement. In some example embodiments (not shown here), each plunger in the respective pair of plungers may be connected to the other via a mechanical linkage, such that their relative movements be maintained uniform. In such embodiments, there is no separate actuator for each plunger, but a single actuator can be used for each respective pair, and thanks to a mechanical linkage, each plunger moves accordingly.

Furthermore, as indicated above, the control unit 195 control the operation of the plunger based on a desired shape to be generated. In other exemplary embodiments, the assembly 1950 rotated as needed during the deposition operation to achieve a desired shape. That is, the assembly 1950 may be coupled to a rotary motor and / or a robotic arm (or other similar moving device), and the control unit 195 (or other system controller) may cause the assembly to rotate as needed, and may activate each of the plungers to achieve the desired consumable and thus the desired deposition shape.

22 shows another exemplary embodiment of a consumable 2000 that can be used with exemplary embodiments of the present invention. The consumables 2000 contains a similar braided structure of wires 2003 with a room 2010 as described above, but also includes a sheath 2015 , The jacket 2015 may be constructed and configured in a similar manner to known cladding structures used for welding or brazing consumables. As shown, in this embodiment, the sheath encloses 2015 the wires 2003 completely and has a seam 2017 which is a butt joint. The jacket 2015 can be made of any material that is to be deposited on the workpiece. In some embodiments, the sheath may 2015 the same material as the wires 2003 while in other embodiments, the sheath may be made of a different material or may have a different composition. The jacket 2015 can also help with that consumable 2000 it retains its shape after being hit by the plungers in the contact tip assembly 21A and 21B was reshaped. More precisely, it causes the wire to squeeze through the mouth 1951 that is the sheath 2015 plastically deformed, which causes the consumable material 2000 maintains the desired shape more easily. That may allow the board of consumables 2000 grows larger during a deposition process.

23 shows another exemplary consumable 2100 that can be used with embodiments of the present invention. The consumables 2100 contains a sheath 2110 and a core 2120 , where the sheath 2110 has a lower melting temperature than the core 2120 , Due to such a different melting temperature, embodiments of the consumable 2100 to provide better control over the manufacture of a component. In embodiments where the consumable melts entirely at generally the same temperature, the dynamics of the molten puddle produced plays an important role in the deposition and build process. In certain cases, the control of the puddle may be difficult, especially in high-precision manufacturing processes or when the thickness of the manufactured workpiece is very thin. In such applications, puddle dynamics can be difficult to control and account for. However, if the consumables 2100 is used, then melts the sheath 2110 in front of the core 2120 , The molten shell material then forms a molten matrix to adhere the core material to the workpiece. In such applications, the importance of the puddle decreases, and in some cases the puddle can be dispensed with. Furthermore, in alternative embodiments, the size and / or depth of the puddle may be reduced as the puddle and molten shell material cooperate to adhere the core material to the workpiece. Therefore, the dynamics of the puddle may be of less importance when the consumables 2100 is used.

In exemplary embodiments, the core 2120 a solid core while in other embodiments the core 2120 Powder or particles of a desired material may be. In such embodiments, the consumable 2100 be shaped (as discussed above) to achieve a desired deposition. That is because the core 2120 Powder or grainy may be the exterior of the consumable 2100 be shaped and crushed to achieve a desired consumption profile. In further embodiments, the consumable may be constructed as that which is at least in 22 wherein the sheath surrounds a plurality of individual wires and at least some (or all) of the wires 2003 have a melting temperature higher than that of the cladding 2015 is. In some such embodiments, even the wires 2003 have different melting temperatures relative to each other. For example, a first number of wires 2003 have a first melting temperature (which is higher than the melting temperature of the jacket), and a second number of wires 2003 may have a melting temperature that is either higher or lower than the melting temperature of the first number of wires 2003 is. Such embodiments may provide increased flexibility in the melt and build profile of the consumable. Further, in some embodiments, the heat source (eg, a laser) and / or the current is controlled such that at least a portion of the core 2120 is also melted during the deposition process. However, in other embodiments, the material of the core becomes 2120 not melted during the deposition process. That is, the sheath 2110 is melted, and the liquid coating material is used to hold the unmelted core material to the workpiece. In such embodiments, the workpiece is produced in layers with molten shell material and core material alternating. It should be noted that 23 although the consumables 2100 with a circular cross-section shows, however, that embodiments of the present invention are not limited in this respect. The consumables 2100 can also have any desired shape as needed, which benefits the structure of the workpiece. For example, the consumable material 2100 have a square, rectangular, polygonal or elliptical cross-section. Of course, other shapes can also be used.

In exemplary embodiments, the materials of the sheath 2110 and the core 2120 chosen such that the sheath 2110 melts at a temperature which is in the range of 5 to 45% below the temperature of the core material. In further exemplary embodiments, the melting temperature of the sheath is 2110 in the range of 10 to 35% below that of the core material. Of course, the exact composition of the sheath and core materials must be selected based on the desired composition and construction of the assembled workpiece.

24A shows another exemplary embodiment, wherein the consumable material 2200 has a non-circular cross-section, and the sheath material 2210 does not cover the entire circumference of the consumable 2200 , That is, the consumable 2200 has an asymmetrical cross-section. For example, in the embodiment shown, the sheath material 2210 only on one side of the core material 2220 of consumables. 24B shows another such exemplary embodiment, wherein the overall shape of the consumable is a hexagon and the sheath material 2210 ' only 5 sides of the hexagonal cross section of the core 2220 ' covered. Of course, other shapes and coatings may be used based on the desired performance and deposition characteristics of the consumable. 24C Another exemplary embodiment is a consumable 2200 '' with a symmetrical cross section, but the distribution of the cladding material 2210 '' and the core material 2220 '' is not symmetrical. This configuration allows you to use the consumables with contact tips and equipment designed for typical symmetrical consumables, but the consumables themselves are asymmetrical. In such embodiments, the sheath material melts 2210 and ensures the adhesion of the core section 2220 consumables, but does not melt away from the total amount of consumables. In such embodiments, the consumable may be aligned as needed prior to adhesion during the deposition process. The sheath material acts as an adhesive material that binds or bonds the core material to the workpiece. Furthermore, in such embodiments, the power or heat input is controlled so that the desired melting of the cladding material is achieved without complete melting of the core material.

24D is another exemplary embodiment of a consumable 2200 ''' that can be used with embodiments of the present invention. The consumables 2200 ''' is similar to those discussed above, except that the cladding layer 2210 ''' has a layered structure. In such embodiments, the cladding layer 2210 '' either a solid material or may be a flux. In practice, in any of the embodiments discussed above, the cladding layer may be a flux and need not be a solid metallic cladding. In these embodiments, it may be desirable, in some applications, to place a material in the flux jacket which should not be melted (or whose melting should be minimized) during the deposition process. To accomplish this, some embodiments use a layered jacket or layered flux 2210 ''' , wherein the composition of the flux directly on the surface S of the core 2220 ''' another is the chemical composition of the flux at the outer edge of the flux. This is in 24D as layers A and B, wherein layer A has a first composition and layer B has a second composition. For the production of these layers known deposition techniques can be used, which need not be discussed in the present text. This type of construction allows materials in the layer B of direct heat in the core 2220 ''' which otherwise melt components in layer B. would. For example, it may be desirable to deposit tungsten carbide in the puddle, which could easily melt when in direct contact with the core 2220 ''' would. In this embodiment, the layer A acts as a heat buffer, allowing the materials of layer B to be deposited at best with little melting. Of course, it is understood that the demarcation between the two layers A and B need not be a clear, precise line, but that a transition from one composition to another can take place. Furthermore, the shape and relative cross-sectional area of layer B relative to layer A may be determined based on the desired composition of the application. 24D is shown as an exemplary embodiment, and other shapes and configurations may be used without departing from the spirit or scope of the present invention.

A computer coupled user interface illustrates one possible hardware configuration for supporting the systems and methods described herein, including the controller 195 , or similar systems used to control and / or operate the systems described herein. To provide additional context for various aspects of the present invention, the following discussion is intended to provide a brief, general description of a suitable computing environment in which the various aspects of the present invention may be implemented. Those skilled in the art will recognize that the invention may also be implemented in combination with other program modules and / or as a combination of hardware and / or software. Generally, program modules include routines, programs, components, data structures, etc., that perform certain tasks or implement certain abstract data types.

Moreover, those skilled in the art will recognize that the inventive methods may be practiced with other computer system configurations, including single processor or multiprocessor computer systems, minicomputers, mainframes, and personal computers, handheld computing devices, microprocessor-based or programmable consumer electronics, and the like, each including a or several associated devices can be operatively coupled. The illustrated aspects of the invention may also be practiced in distributed computing environments where certain tasks are performed by remote processing devices that are interconnected via a communication network. In a distributed computing environment, program modules may be located in both local and remote storage devices.

The control unit 195 For example, an example environment may be used to implement various aspects of the invention, including a computer, wherein the computer includes a processing unit, a system memory, and a system bus. The system bus couples system components, including, for example, the system memory, to the processing unit. The processing unit may be any of various commercially available processors. Dual microprocessors and other multiprocessor architectures may also be used as the processing unit.

The system bus may be any of various types of bus structure, including a memory bus or memory controller, a peripheral bus, and a local bus employing a variety of different commercial bus architectures. The system memory may include read only memory (ROM) and random access memory (RAM). A Basic Input / Output System (BIOS) that contains the basic routines that help transfer information between elements within the computer, such as during startup, is stored in ROM.

The control unit 195 may further include a hard disk drive, a magnetic disk drive, for example, to read or write a removable disk, and an optical disk drive, for example, to read a CD-ROM disk or to read and write other optical media. The control unit 195 can contain at least one form of computer-readable media. Computer-readable media can be any available media that the computer can access. As non-limiting examples, computer-readable media may include computer storage media and communication media. Computer storage media includes volatile and nonvolatile, removable or non-removable media implemented in any methods or technologies for storing information such as computer readable instructions, data structures, program modules, or other data. Computer storage media include, for example, RAM, ROM, EEPROM, flash memory or other storage technologies, CD-ROMs, Digital Versatile Disks (DVD), or other magnetic storage devices or other media that may be used to store the desired information and which may be accessed by using the control unit 195 coupled user interface can be accessed.

Communication media typically embodies computer readable instructions, data structures, program modules, or other data in a modulated data signal, such as a carrier wave or other transport mechanisms, and includes any information delivery media. The term "modulated data signal" means a signal in which one or more of its characteristics are adjusted or changed in such a way as to encode information in the signal. As non-limiting examples, communication media includes wired media, such as a wired network or a direct-wired connection, and wireless media, such as acoustic, RF, infrared, and other wireless media. Combinations of the above are also included in the scope of computer-readable media.

A number of program modules may be stored in the drives and RAM, including an operating system, one or more application programs, other program modules, and program data. The operating system in the computer or the user interface 300 can be any of a number of commercially available operating systems.

Furthermore, a user may enter commands and information into the computer with a keyboard and a pointing device, such as a mouse. Other input devices may include a microphone, an infrared remote control, a trackball, a pen input device, a joystick, a game pad, a digitizer tablet, a satellite dish, a scanner, or the like. These and other input devices are often connected to the processing unit through a serial port interface coupled to the system bus, but may also be connected through other interfaces, such as a parallel port, game port, universal serial bus (" USB "), an IR interface and / or various wireless technologies. A monitor or other type of display device may also be connected to the system bus via an interface, such as a video adapter. Visual output can also be achieved with a remote display network protocol, such as a Remote Desktop Protocol, VNC, X Window System, and so forth. In addition to visual output, a computer typically also includes other output peripherals, such as speakers, printers, etc.

A display panel may be one with the control unit 195 coupled user interface may be used to present data that is received electronically from the processing unit. For example, the display panel may be an LCD, plasma, KSR, or other monitor that presents data electronically. Alternatively or additionally, the display panel may present received data in a printed format, such as a printer, a fax, a plotter, etc. The display panel may present data in any color and may communicate data from a user interface via any wireless or hard-wired protocol / or receive any wireless or hardwiring standard.

The computer may operate in a networked environment using logical and / or physical connections to one or more remote computers, such as one or more remote computers. The one or more remote computers may be a workstation, a server computer, a router, a personal computer, a microprocessor-based entertainment device, a peer device or other common network node, and typically include many or all of the elements that comprise with reference to the computer. The logical connections shown include a local area network (LAN) and a wide area network (WAN). Such networking environments are commonly found in offices, enterprise-wide computer networks, intranets, and the Internet.

When used in a LAN network environment, the computer is connected to the local area network via a network interface or adapter. When used in a WAN network environment, the computer typically includes a modem, or is connected to a communication server in the LAN, or has other means of establishing communication over the WAN, such as the Internet. In a networked environment, program modules shown with respect to the computer or portions thereof may be stored in the remote storage device. It should be understood that the network connections described herein are exemplary and that other means of establishing a communication link between the computers may be used.

Although the invention has been described with reference to specific embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from its scope. Therefore, it is intended that the invention not be limited to the specific embodiments disclosed, but that the invention includes all embodiments falling within the scope of the appended claims.

LIST OF REFERENCE NUMBERS

100

system

110

laser beam

115

Workpiece or deposition layer

120

laser device

125

direction

130

power supply

140

Cored wire or consumable

140 '

Wire or consumable

140 ''

consumables

140 '' '

consumables

150

Fülldrahtzufuhrvorrichtung

160

Contact tube or tip

170

power supply

170 '

Background Power Supply

180

Motion controller

190

robot

195

Subsystem or controller

300

User interface

400

waveform

401

Impulse

402

rising portion

402A

Slew rate

402B

Slew rate

402C

Slew rate

404

descent section

405

first level

407

Transition point

410

waveform

411

Impulse

413

current level

510

waveform

511

Point

520

waveform

525

rise

530

time interval

540

value

550

level

700

system

701

section

703

section

705

insulation section

707

tip assembly

710

combining circuit

800

waveform

801

pulse

803

Background section

810

laser power

811

step

812

step

813

Peak laser power level

814

Point

815

step

816

step

817

Point

820

Wire feed speed

821

step

821 '

puddle

822

Peak wire feed speed

823

Wire feed speed

824

wire

825

Tip retraction speed

826

step

827

Point

830

heating current

831

Point

833

peak level

834

upper point

835

descent

836

Restrike current level

837

power supply

840

tension

841

wire

842

Peak voltage level

843

waste

844

level

845

step

846

peak level

847

Arc suppression routine

848

Arc detection voltage level

900

exemplary system

901

conductive section

903

insulation section

905

conductive section

910

contact tip

1000

exemplary system

1010

Contact tip assembly

1100

system

1110

heat sensor

1120

temperature sensor

1200

exemplary system

1210

power supply

1220

user input

1221

positive connection

1222

negative connection

1223

Abfühlanschlussdraht

1230

CPU / controller

1240

Voltage detection circuit

1250

power module

1300

exemplary system

1303

contact tip

1303 '

contact tip

1303 ''

contact tip

1303 '' '

contact tip

1305

Contact tip assembly

1310

Power system

1311

Power supply module

1312

Power supply module

1313

Power supply module

1314

Power supply module

1320

actuators

1600

exemplary substrate

1603

non-conductive matrix

1605

conductive particles

1610

non-bonding surface

1620

contact zone

1625

ground point

1630

grid

1640

cooling channel

1651

ground point

1652

ground point

1653

ground point

1660

combining circuit

1670

ladder

1800

stiffening structure

1810

support component

1820

support component

1825

contact point

1830

Contact projections

1900

consumables

1900 '

consumables

1903

first wire type

1903 '

middle wire

1905

second wire type

1910

core

1950

Contact tip assembly

1951

opening

1953

contact plunger

1955

contact plunger

1956

actuators

1957

preload

2000

Contact tip assembly

2003

wires

2010

Consumable or space

2015

Contact tip section or sheath

2017

seam

2020

consumables

2025

Contact tip portion

2030

muzzle

2040

contact tip

2050

switch

2100

exemplary consumable material

2110

jacket

2120

core

2200

consumables

2200 ''

consumables

2200 '' '

consumables

2210

sheathing material

2210 '

sheathing material

2210 ''

sheathing material

2210 '' '

cladding layer

2220

nuclear material

2220 '

core

2220 ''

nuclear material

2220 '' '

core

A

Puddle or layer

B

layer

D

droplet

L No. 1

first shift

L No. 2

second layer

L No. 3

third layer

LM

fourth shift

OCV

Open circuit voltage

S

Substrate or surface

Ta

Period

Tr

Wire return period

X

Vorstehdistanz

Claims (15)

An additive manufacturing system comprising: a high energy device that irradiates a surface of a workpiece with a high energy discharge to form a first and a second molten puddle on a surface of the workpiece; a first power supply feeding a first heating signal into a first wire, wherein the first heating signal comprises a plurality of first current pulses and wherein each of the first current pulses of the first heating signal generates a molten droplet at a distal end of the first wire which is deposited into the first puddle ; and a second power supply feeding a second heating signal into a second wire, the second heating signal comprising a plurality of second current pulses, and wherein each of the second current pulses of the second heating signal produces a molten droplet at a distal end of the second wire which is deposited into the second puddle ; and wherein each of the first current pulses reaches a peak current level after a distal end of the wire has touched the first puddle, wherein the first heating signal has no current between the plurality of first current pulses; wherein the distal end of the first wire does not contact the first puddle between successive peak current levels of the first current pulses; wherein the first power supply controls the first heating current such that no arc is generated between the first wire and the workpiece during the first current pulses; and wherein the first and second molten puddles are distinct molten puddles. The system of claim 1, wherein the first wire has a first wire feed speed and the second wire has a second wire feed speed different from the first wire feed speed. The system of claim 1 or 2, further comprising a first contact tip for the first wire and a second contact tip for the second wire, the first and second contact tips feeding the first and second heating signals into the first and second wires, respectively; and wherein the first and second contact tips are movable relative to each other. The system of any one of claims 1 to 3, further comprising a first contact tip for the first wire and a second contact tip for the second wire, the first and second contact tips providing the first and second heating signals, respectively, to the first and second wires and wherein the first wire has a first protruding distance different from a second protruding distance for the second wire. The system of any one of claims 1 to 4, further comprising a first contact tip for the first wire and a second contact tip for the second wire, the first and second contact tips providing the first and second heating signals, respectively, to the first and second wires and a contact tip assembly that couples the first and second contact tips together, wherein the contact tip assembly is rotatable relative to a feed direction of the first and second wires. The system of any one of claims 1 to 5, wherein the first power supply monitors a voltage of the first heating signal when the first wire is in contact with the first puddle and compares the voltage to an arc detection voltage level. An additive manufacturing process comprising: Irradiating a surface of a workpiece with a high energy discharge to form a first and a second molten puddles on a surface of the workpiece; Feeding a first heating signal into a first wire, the first heating signal including a plurality of first current pulses, and wherein each of the first current pulses of the first heating signal generates a molten droplet at a distal end of the first wire deposited in the first puddle; and Feeding a second heating signal into a second wire, wherein the second heating signal comprises a plurality of second current pulses, and wherein each of the second current pulses of the second heating signal generates a molten droplet at a distal end of the second wire which is deposited in the second puddle; and wherein each of the first current pulses reaches a peak current level after a distal end of the wire has touched the first puddle, wherein the first heating signal has no current between the plurality of first current pulses; wherein the distal end of the first wire does not contact the first puddle between successive peak current levels of the first current pulses; wherein the first heating current is controlled such that no arc is generated between the first wire and the workpiece during the first current pulses; and wherein the first and second molten puddles are distinct molten puddles. The method of claim 7, wherein the first wire is fed at a first wire feed speed and the second wire is fed at a second wire feed speed different from the first wire feed speed. The method of claim 7 or 8, further comprising passing the first wire through a first contact tip and passing the second wire through a second contact tip, wherein the first and second contact tips apply the first and second heating signals, respectively, to the first and second contactors Feed wire, and move the first and second contact tip relative to each other. The method of claim 7, further comprising passing the first wire through a first contact tip and passing the second wire through a second contact tip, the first and second contact tips injecting the first and second heating signals, respectively, into the first and second contact tips feeding the second wire, and wherein the first wire is held at a first protruding distance different from a second protruding distance for the second wire. The method of claim 7, further comprising passing the first wire through a first contact tip and passing the second wire through a second contact tip, the first and second contact tips injecting the first and second heating signals, respectively, into the first and second contact tips feed the second wire and rotate the second contact tip relative to the first contact tip during additive manufacturing. The method of claim 7, further comprising: monitoring a voltage of the first heating signal when the first wire is in contact with the first puddle and comparing the voltage with an arc detection voltage level. A method or system according to any one of claims 1 to 12, wherein the stand-alone molten puddles lie side by side on the workpiece. The method or system of any one of claims 1 to 13, wherein the first and second wires are positioned on a line in a feed direction, and wherein the second wire is the first one Wire lags and the second wire is positioned so that it is deposited on a layer that was created by the first wire. The method or system of any one of claims 1 to 14, wherein the first wire has a different composition than the second wire.

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