JPH06507347A - Method and apparatus for producing metal matrix composite material using electromagnetic body force - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] Background of the invention of method and device for manufacturing metal matrix composite materials using electromagnetic body force The present invention utilizes electromagnetic body force to push molten metal into a reinforcing material. Concerning the manufacture of materials.

Strong ceramic phases that harden metals, such as modern carbon or alumina fibers The remarkable structural materials that can result from reinforcement by There is a great deal of interest in developing new manufacturing routes. To manufacture such materials Of the countless methods in use, casting stands out as the most attractive. . Light matrices such as aluminum offer low cost and their potential for reticular component forming processing. That's why it's popular. These methods have recently been proposed by Mortensen et al. 40 Journal of Metals 2. February 1988, 12- (page 19). , Currently, methods for casting metal matrix composite materials include: (1) the liquid metal material is the reinforcing material; to overcome the capillary forces at its penetration front as it advances into the (i i) Processing time and therefore cost and chemistry of the matrix and reinforcing materials in the reaction system The applied pressure is used to minimize both the extent of reaction. metal processing Compression can be done by mechanical means, such as a piston (as in draw casting) or a pressurized gas. (as in the clay method). Thus, it is sold in large quantities. Toyota's aluminum base metal component is selectively reinforced with alumina fiber. Draw casting currently used to form diesel engine pistons Many infiltration devices have been designed, such as presses.

R ox 9 fruit leopard A novel method for forcing molten metal into preformed reinforcement using electromagnetic body force The method and apparatus are described. Electromagnetically induced body force can be used in other applications such as electroforming of solid metals. Used in material processing operations, such forces can force the flow of liquid metal into particles, fibers, etc. This is the first time to manufacture composite materials by reinforcing materials such as preforms or reinforcing materials. used here. According to the invention, sufficiently strong electric and magnetic fields interact to Produces electromagnetic body force on metal. This force is used to propel the liquid metal in a selected direction You can. The use of such forces is an efficient method of manufacturing metal matrix composites. It is. According to one embodiment, the electric and magnetic fields are applied to a liquid forming the matrix of the composite material. can be produced by the discharge of an electric current through a coil of conductive material in the vicinity of a metal . This current creates a transient magnetic field B within a certain thickness of the metal, and the magnetic field B A transient eddy current j is formed in the molten metal. These two fields in the molten metal are A body force called body force F=jxB is formed, and this force forces the base body into the preform. used to promote

In general, in one aspect, the present invention provides a method for manufacturing a metal matrix composite material. In the process, a substantially liquid metal is used as a reinforcing material and becomes sufficiently inert when activated. be placed close to the source of the transient magnetic field to detect the transient magnetic field and the induced into the metal by this transient magnetic field. Generate electromagnetic body force within the metal through the interaction of guided eddy currents, and Activating a passing magnetic field, which drives the substantially liquid metal into the reinforcing material. The method includes:

In a preferred embodiment, the activation step is repeated and a large amount of liquid metal and reinforcing material reinforcing material in which the metal is continuously supplied and the metal is propelled from the vicinity of the source of the transient magnetic field. metals such as aluminum, nickel, cobalt, and steel. , beryllium, lead, tin, zinc, magnesium, titanium, or iron. or an alloy thereof, the reinforcing material includes ceramic, and the reinforcing material Reinforcement materials include fibers, whiskers, grains, platelets, or rods. The reinforcing materials are silicon carbide, boron, tungsten, carbon, silicon nitride, boron carbide, silicon oxide, aluminum oxide, titanium, or steel The propulsion step further includes subjecting the substantially liquid metal to an electric field. The transient magnetic field is generated by a discharge coil through which a current passes and is repeatedly activated. The frequency and attenuation constant of the converted transient magnetic field are determined by the shape of the discharge coil, the reinforcing material, the shape of the metal, and the current is an oscillating current adapted to the depth at which the metal is propelled into the reinforcing material. , the transient magnetic field is generated by a discharge coil coupled to a magnetic flux concentrator through which the current passes. The flux concentrator contains copper or graphite to reduce the penetration depth of the transient magnetic field into the reinforcing material. Is the thickness less than the thickness of the liquid metal plus the part of the reinforcing material penetrated by the metal? Or approximately equivalently, this method allows the electric current to penetrate the reinforcing material of the magnetic field to a depth that is similar to that of the liquid metal. less than the thickness plus the area where the reinforcing material is penetrated by the metal, or The currents are greater than or approximately equal to the currents required to maintain them approximately equal. It involves adjusting the frequency of the current, and is connected to the discharge coil by one or two capacitors. A current is applied to the discharge coil so that it substantially surrounds the liquid metal and reinforcing material. The discharge coil is of the solenoid type, and the discharge coil is substantially flat. A flat helical coil, a substantially flat helical coil having one side of substantially liquid metal , the propulsion is from one side of this substantially liquid metal on the other side. a disposed cooling source cools the composite material after the metal is propelled into the reinforcing material; Substantially flat helical coils are then disposed on either side of the reinforcing material.

In yet another aspect, the invention provides a method for manufacturing a metal matrix composite material. a quantity of substantially solid metal is placed in a heat-resistant container, and the metal is substantially Heat the metal to a liquid state and immerse the reinforcing material preform into this metal. This heat-resistant container containing a strong material should be placed near a source of inert transient magnetic fields that will become sufficient when activated. The phase of the transient magnetic field and the eddy currents induced in the metal by this transient magnetic field This generates an electromagnetic body force within the metal through interaction and activates a transient magnetic field, which The method includes driving metal into a reinforcing material by a method.

In yet another aspect, the invention provides a method for manufacturing a metal matrix composite material. the reinforcing material is placed in a heat-resistant container, and the reinforcing material is placed in a quantity of substantially solid metal. The metal is heated to a substantially liquid state, and the heat-resistant container is heated to an activated state. be placed in close proximity to a source of inert transient magnetic fields that will be sufficient to electromagnetic body force in a metal through the interaction of eddy currents induced in the metal by a field. generates and activates a transient magnetic field that propels the metal into the reinforcing material. The method includes:

In yet another aspect, the invention provides a method for continuous production of metal matrix composites. conveying the substantially liquid metal to the infiltration zone, and transferring the reinforcement material to the infiltration zone. and in the vicinity of the liquid metal, subjecting the liquid metal to a magnetic field. The step of infiltrating the reinforcing material with the liquid metal and the infiltrated composite material in the infiltration area The method includes the step of transporting the container out of the area.

In a preferred embodiment of this aspect, the reinforcing material is particles, fibers and -1 whiskers. , or bars, the particles include silicon carbide particles, and the fibers include carbon fiber particles. The fibers containing the bar and delivered to the infiltration area are uniaxially oriented and during the infiltration stage, This axle orientation is maintained.

In yet another aspect, the invention provides a method for manufacturing metal matrix composite materials using electromagnetic body force. In an apparatus for and a source of electromagnetic fields that can be activated and deactivated, the liquid gold in the permeation region an electromagnetic field source adjacent to the metal subregion that generates transient magnetic fields and associated eddy currents within the metal. an electromagnetic field source oriented to propel the metal into the reinforcing material sub-region of the penetration region. Features an apparatus including:

In a preferred embodiment of this aspect, the electromagnetic field source surrounds the penetration area and the electromagnetic The field source includes a discharge coil and the electromagnetic field source includes a helical coil adjacent to one side of the penetration area. The device further includes a small capacitor bank and a capacitor bank. The circuit that flows when the sabank discharges current through the discharge coil contains a circuit that The device further includes a magnetic flux concentrator connected to the discharge coil, which focuses the magnetic flux. The vessel contains steel or graphite, the penetration area is defined by a heat-resistant crucible, The reinforcing material is a preform and the crucible includes the preform in the permeation zone and Contains equipment for raising and lowering the preform into the permeation area and the device for raising and lowering from the permeation region includes a bobbin centered within the crucible. The bobbin directs the flow of metal propelled by an electromagnetic field source away from the central axis of the crucible. radiating direction, the penetration area is defined by a heat-resistant tube, and and further includes a conveying device for conveying the reinforcing material through the heat-resistant tube. I'm reading.

In yet another aspect, the present invention provides a method for manufacturing a metal matrix composite material using an electromagnetic component J. In an apparatus for fabricating a permeable region with adjacent liquid metal and reinforcing material heating device surrounding the permeation region and located within the liquid metal sub-region of the permeation region. A heating device capable of maintaining the metals in a liquid state, and activating and deactivating them. an electromagnetic field source adjacent to the liquid metal sub-region of the permeation region that can be An electromagnetic field source that generates a passing magnetic field and associated eddy currents in metal, the discharge coil being an electromagnetic field source oriented to propel the particles into the reinforcing material sub-region of the penetration region; The device is characterized by:

In a preferred embodiment of this aspect, the heating device is a thermostat surrounding the electromagnetic field source. Contains a cut-controlled heating element.

Infiltration by this method and using this device has many advantages. electromagnetic volume The force literally propels the metal into the reinforcing material. Pushing the metal into the reinforcing material other pressure-inducing devices and pressure-resistant or Eliminates the need for pressure containment vessels.

Penetrating metal rates are potentially high and can be controlled by controlling electrical pulses and magnetic fields. Rukoto can. Friction or loss of pressurized gas can also reduce the efficiency of the infiltration process. We now turn to the structure and operation of the preferred embodiment, beginning with a brief description of the drawings. .

FIG. 1 is a cross-sectional view of an apparatus for producing cylindrical or tubular metal matrix composite materials. , FIG. 2 is a cross-sectional view of an apparatus for producing a -V curved metal matrix composite material, and FIG. are micrographs of composite materials produced according to the present invention, and FIG. 3 is a higher magnification micrograph of the composite material of No. 3.

FIG. 5 compares the magnetic flux density of the search coil with that of a damped sine wave.

Figure 6 shows the magnetic flux distribution in the furnace for different discharge voltages (device i!l ).

Figure 7 shows the stress-strain curves for 24 volume percent Safill 1 at 673 °K. It is.

Figure 8 shows the distance that the preform is penetrated over the course of a typical discharge. There is.゛ Figure 9 shows the cumulative penetration distance after each of nine 3KHz discharges.

Figure 10 shows the cumulative penetration distance after each of 50 5.6 KHz discharges. .

Figure 11 shows the expected penetration distance after five discharges with a 3 Tesla peak. ing.

Metal matrix composites may be formed in the devices shown in FIGS. 1 and 2. . 7 What both have in common is the function of the electric component that generates electromagnetic body force. but While the composition of these components depends on the shape of the composite material from which their composition is to be manufactured, As the heating components are determined by

In FIG. 1, the copper discharge coil 22 is connected to the 640 mm through any conventional trigger circuit. A bank of capacitors (not shown) with a total capacitance of 4.5 kg Oo 25 is electrically connected to a power source (not shown) capable of generating a robot. The coil 22 is made of inch (0,635 cm) copper wire and is configured as a solenoid. to focus the magnetic field generated by the energized discharge coil 22; A copper magnetic flux concentrator 21 is provided. The height of the inner radius of the concentrator 21 is - of the height part of the diameter, and as a result the penetration defined by the internal height The magnetic flux is increased by about 300% in the area.

Magneform Corporation (now California) for the electromagnetic formation of solid metals. Units manufactured by Maxell Laboratories, Sun Diego, N.A. also have higher It is used in the above coil to obtain wave number discharge. This unit is the first device has a lower capacitance, but requires a higher current for comparable peak flux values. charge to pressure. The total stored energy at full voltage of the Magneform machine is 8 This is K.J. This Magneform device uses several ignitron tubes. I'm there.

Focuses the magnetic field close to the molten metal surface and generates a sufficiently high field strength Compromises must be reached in the design of the coil to maintain a high enough frequency for No. In this work, coils with 6 to 18 turns are used.

These heating components form the bulk of the embodiment of FIG. insulated chang The bar 2 includes an insulating lid 12, an insulating bottom 32, and a wall 30. The heat insulating material 28 generates heat. It surrounds the body 26. The discharge coil 22 enclosed in heat-resistant cement is a magnetic It surrounds the bundle concentrator 21.

In a preferred embodiment, SUPHIL™ alumina fibers having silica bonded to them A preform 18 of reinforcing material, such as a bar, is inserted into the crucible 20. Prefo to ensure that the beam 18 remains precisely centered within the crucible 20. 1, which is attached to a bobbin 19 as shown in the apparatus of FIG.

This configuration has several additional advantages. In other words, the infiltrated composite material is While it is melting, it can be removed from the crucible, and the flange of the bobbin allows the metal to be Since it is easy to suppress the flow in the radial direction, the axial flow can be minimized. .

Several bobbin designs are used, all of which are functionally equivalent. Only the material selected differs; the central rod can be steel or high-density alumina. reactor. These fiber preforms are infiltrated along their pressurized planes. Ru.

The crucible 20 is preferably made of heat-resistant ceramic such as alumina. one implementation In the example, fused alumina 16 is placed in a crucible overlying the Pour around the preform. Insulation plate to prevent stray metal flow during infiltration A lug 14 overlies the preform/melt mixture. The crucible with a lid is The crucible lift mechanism 34 then passes through the opening 7 into the central cavity of the chamber 2. It will be lowered to 5.

In another embodiment, the required amount of alumina is first added to each crucible and the alumina It is placed together with the plug in a holding furnace (not shown) set at 973°K.

The preform already installed in its bobbin is Once it began to melt in the crucible, it was placed in a furnace. Once the metal is completely melted , the preform-bobbin assembly was immersed in the melt and allowed to equilibrate for 5 minutes. It was. The crucible with its preform is removed from the holding furnace and 973 .

It is lowered into an infiltration furnace which is preheated to K. At this point, the ceramic plastic The plug is pushed into the top of the crucible so that it rests on top of the melt surface.

When a charged capacitor is discharged through the discharge coil 22, a very high voltage is applied to the coil. A high pulse current is generated, which causes the current to flow inside the crucible 20 via the concentrator. Correspondingly high transient magnetic fields occur. A magnetic field of about 2 to 10 Tesla is used. However, depending on other system variations, higher or lower magnetic field strengths may be used. I can do it. Currents of about 20,000 to about 50,000 amperes are used. However, this can also be higher or lower in other systems.

Preferably, the penetration depth of the magnetic field into the molten metal is not greater than the total thickness of the layer of metal. . By increasing the frequency of the current, the penetration depth of the magnetic field decreases, which is This is one way to make the location adaptable to a variety of possible shapes.

The transient magnetic field conducts an electric current into the molten metal 16, which is drawn by the coil 22. Interact with the generated magnetic field. This interaction causes the preform 18 to A net-like body force is generated in the molten metal 16, and the molten metal is transferred to the coil 22 and the magnetic flux Push it out from the container 21 and push it into the pre-form. Due to many discharges This ensures that the liquid penetrates to the desired depth within the preform. Against liquid penetration The capillary and frictional forces involved are insufficient to prevent significant penetration of the preform.

Room temperature coils have also been used. This step involves placing the heated crucible in a cold concentrator. Freezing of the melt is expected to begin in 45-60 seconds after being introduced into the Therefore, the crucible should be returned to the holding furnace within 30 seconds of its transfer to the discharge coil. Equivalent to the procedure above, except that The period of this 30 second time interval The number of discharges possible during the period varies from 3 to 8 depending on the voltage of the discharge. Thus , some of these samples may have to be reheated more than once to obtain the required number of discharges. I had to.

The current produced by this device is a sinusoid that decays exponentially after the first half cycle. It has wave characteristics. A typical magnetic flux distribution is shown in FIG. These controllers The voltage at which the capacitor is charged can vary and is one of the key process parameters; , since this determines the strength of the magnetic pulse. These conde As soon as the sensor recharges (2 to 5 seconds in laboratory equipment), repeat the discharge. I can do that. Other characteristics of the pulse, such as its frequency and damping constant, The electrical circuit is largely determined by the module coil and capacitance design. depending on the capacitance, inductance, and resistance of the path. The shape of this process Although the shape is flexible, this means that the coil, crucible, and preform are cylindrical. This is because there is no need. Through a quantitative understanding of its dynamics, the penetration length can also be precisely controlled. You can control it.

In order to know the precise shape of the magnetic flux density B generated in the concentrator as a function, the period of discharge Measure the voltage across the resistor through which the primary coil current flows using a digital oscilloscope. A signal proportional to B is obtained by for a given frequency (because the performance of the concentrator varies with frequency), the magnetic flux density depends on the primary coil current. Proportional.

A search coil is designed that produces a voltage signal proportional to the time derivative of the magnetic flux density. Ru. This search coil is attached to an RFL Model 912 Gaussmeter in Borough, Georgia. Calibrated against RFL Industries, Inc. This allows magnetic Assuming that the first peak of the field is a sine wave, the peak magnetic field strength B. The measurement of Now possible (Figure 5). This B. The value of , in combination with the output from the resistor, is the time Give the curve versus magnetic field. Bo is for each set of coils and concentrators used. It is calibrated as a function of the peak intensity measured by the transducer.

To calibrate these furnaces at 973 °K, a thermally and electrically insulating strip The sleeve is placed over the search coil, allowing the search coil to take each measurement. It is made to withstand the temperature in an empty oven for several seconds. Then the result Resulting current peak intensity vs. B. The curve of the magnetic probe is used during the penetration experiment. The pulsating magnetic field distribution has been determined without using

Magnetic flux density traces for several discharge voltages are connected to the first mentioned device. 6 for an 18-volume furnace. With this configuration, 1. 52K A fundamental frequency of Hz is given, where the fundamental frequency is equal to the second and all subsequent half frequencies. is the discharge frequency of the cycle. For each combination of coil and machine, H is exponential varies in time as a sine wave that decays to , but after the first half cycle the frequency increases to It's changing.゛ A process model is created using these data. Furthermore, preform Mechanical properties have been measured. Engineering correct force curve e = (hho) / h3 '.

(where h is the height of the preform during the test and ho is the height of the initial preform height) is given in FIG. The resulting curve is below 7MPa appears to be sub-order to the distortion.

The penetration distance for a sample of 24% by volume Sapphire T' infiltrated with aluminum is Table 1 shows each preform diameter, discharge energy and discharge frequency. .

Samples 20 and 21 are oriented in the direction midway between their lengths of the diameter of the preform. shows a significant decrease in For more discharge of these samples, pre The foams can be removed from the melt, indicating that they have collapsed.

Substantially complete infiltration is achieved by following the above procedure in composites produced in this manner as shown in Figures 3 and 4. This can be achieved by implementing the following steps. 100 times The micrograph in Figure 3 taken at a magnification of 1.000x and the hole in Figure 4 taken at a magnification of It shows gender.

The samples shown in Figures 3 and 4 are aluminum-infiltrated SAFIL 1 alumina preforms. It's about form. The cylindrical preform has a diameter of 16 mm and a length of 5 cm. 3 μm diameter fiber with 4% silica added as binder have. After placement into the crucible and in the penetration area where the magnetic field is the longest, 1 Zero pulses of current were discharged through the coil at 4 second intervals.

Each created a magnetic field with a strength of about 4 Tesla. 3000 volts each Luz vibrated with a frequency of approximately 3000 hertz. 30,0 by each pulse A current of 0.00 amperes was generated. The temperature of this penetration zone is about 690-710°C. Ta.

Too high field strength or too many pulses may cause undesirable fiber or particle collapse. It can lead to destruction. Therefore, the micrographs of the samples in Figures 3 and 4 show that the fibers are As long as the preform remains intact despite the high rate of infiltration, it will not disintegrate significantly. It shows that there is not, and there is. (There are some destroyed fibers, but these The blend shown in the photomicrograph is typical of pressed virgin preforms. be. ) This preform can be manufactured according to process parameters up to 2.5 mm. It has been penetrated to varying depths.

The prepared sample is completely penetrated to a distance of approximately 300 μm from the penetration front.

The closer you get to the penetration front, the more the porosity gradually increases, resulting in a relatively sharp penetration front. reach. Once the molten metal has penetrated the Fill 1 preform, it will naturally No dehumidification. Therefore, during the period of infiltration, the increased pressure value Provided that the area is also experienced by the metal, the area is completely Keep it infiltrated. The low porosity observed in the preform is due to the Lorentz force ( at relatively high pressures generated by (up to 6 MPa) and low frequencies, As a result of the occurrence of a reversal in the Lorentz force that induces an upward pressure near the penetration front be. Despite the relatively high applied pressure, the long alumina present in the preform The fibers are not destroyed in the infiltrated composite. This is the best penetration At around conditions, the preform deforms to a degree that significantly destroys fibers. This is consistent with calculations that predict that there will be no.

This process involves not only the current passing through these coils (, the number of these pulses, It can be controlled by varying the duration and frequency. The optimal condition is Depending on reform shape and size, fiber or particle size, and base metal composition. and change. The shapes of the coils, crucibles, melts, and preforms also vary. Modifications to reinforcing and parent materials and shapes to optimize penetration I can do it.

Process parameters Figure 8 shows a typical emission at 2, IKHz and 3 Tesla peaks, with a decay rate of 0.5 mS. The graph shows how the penetration distance changes during the period of electricity. body force As it increases, no penetration is expected until the body forces are large enough to overcome the capillary forces. I understand that it is not possible. At this point, fluid friction increases and slows the flow (melting There is a rapid acceleration of the body into preform. The Lorentz force is applied to the melt again. When lowering, it progresses until it stops due to the combined action of fluid friction and capillary force. Even if the forward force is considerably lower than the forward force at this This is because it is assumed that capillary forces do not prevent the receding metal flow.

Figure 9 shows the 2, 3, and and cumulative penetration depth of 1 to 9 discharges for a peak flux strength of 4 Tesla. . This model shows that the increment of penetration from the first few discharges is greater than for subsequent discharges. I expect it to be big. This is clearly due to the shorter penetration length of the initial discharge. This is because the fluid frictional force that must be overcome is low. However, the calculation is After the discharge of , the penetration depth increment per discharge becomes almost constant, and as shown in It only decreases by a very small amount as the transparency progresses. This is because these totals This is the most important discovery in mathematics. In other words, it is possible to subject metal to many magnetic pulses. provided that the equipment is designed and the preform can withstand the forces generated. , the depth of penetration that can be achieved using this process for this system. Theoretically, there are almost no limits. , Figure 9 also shows the optimal emission for a given frequency. This proves that electric strength exists. This effect is due to preform compression m- If the discharge is too strong, the preform will become preformed due to the increased fiber volume fraction. Capillary and fluid friction forces with reduced foam permeability and thus increased propulsive force gain This means that the larger the size, the more it will be compressed.

Figure 11 shows that the 3 Tesla The expected cumulative penetration after five discharges with peaks is shown. very low lap At the wave number, the penetration depth is insufficient for the generated Lorentz forces to overcome the capillary forces. The greater the value, the greater the melt ring thickness, and therefore zero penetration is expected.

At high frequencies, the body force is higher, but its duration is much shorter. Therefore , the inertia is more than the limit for penetration, and as the velocity increases, the liquid composite This leads to an increase in fluid friction losses in the penetration part. These two opposing effects is the expected 1.5KHz for this crucible/'preform shape and penetration. yielding an optimum frequency for a fixed number of discharges around.

Although aluminum was used in the above examples, other base metals could be used. come. Magnesium, lead, tin, zinc, nickel, cobalt, beryllium, titanium , and steel (iron) can be used alone or in the form of an alloy. fibrous, granular, or Silicon carbide, boron, silicon oxide, aluminum oxide, silicon nitride in other forms Materials such as carbon dioxide, boron carbide, silicon oxide, or steel are among other acceptable reinforcing materials. It will be done.

The process of this example is such that the motive coil current is common even in batch mode. Discontinuous in the sense that it is not continuous, but using repeated pulsating currents It is more easily adapted to continuous casting processes. Metals react to body forces rather than ambient pressure. The permeation area can be partially opened and retains pressure. does not need to be adapted as such. These are accessible during the pressurization phase of the process. In order to remain possible, the metal and reinforcing materials are impregnated into the resulting composite material. can be continuously supplied to the percolated area to be extracted by continuously casting Ru. This unenclosed process area also allows very short cycle times However, this can be used to remove any piston, release pressurized gas, or seal it. This is because there is no need to open the container.

Figure 1 shows an example in which the preform is infiltrated in a batch mode; The apparatus can be easily adapted to continuously cast metal matrix composite materials. This fruit In an embodiment, the ceramic crucible is replaced with a ceramic tube. Figure 1 The locations shown are for accommodating continuous lengths of rod or tube preforms. Not only the lid is open, but also the bottom and along its central axis. At the discharge end A cooling zone allows the composite material to solidify before it exits the device and is collected. . A reinforcement preform, such as a rod or hollow cylinder, is fed through the device and Penetrated by the liquid metal as it passes through the penetrating region within the focused magnetic field of the flux concentrator. It will be done.

The shape of the discharge coil, any flux concentrators that may be used, and the heating component are manufactured. It can be modified depending on the type and shape of the composite material to be used. The device shown in Figure 1 cylindrical or tubular composites manufactured using solenoid-shaped coils; The planar composite uses the flat "pancake" helical coil of FIG. In such a configuration Thus, flat substantially two-dimensional products such as preforms having continuous fibers Penetration from one side of the reform is possible.

Figure 2 shows such a furnace with a furnace and coil adapted to produce planar composite materials. The figure shows the equipment used. The heating element 62 within the insulating wall 64 maintains the temperature of the ceramic crucible 54. is held above the melting point of metal 60. The metal 60 and flat preform 52 are placed in a crucible. After placement in the crucible, a heat-resistant plug 50 is placed over the crucible to prevent splashing.

Then, the flat spiral discharge coil 56 embedded in the heat-resistant cement 58 The liquid metal 60 is energized and propelled into the preform.

The composite material produced by the type of manufacturing equipment in Figure 2 is , heat-resistant plug side), which allows for faster solidification of the matrix. is brought about. For example, the heat-resistant plug 50 can act as a chiller; The preform is placed flush with the underside of the plug/cold metal prior to infiltration. Fa Possible fiber collapse due to reduced exposure to high melt temperatures of fibers. Fracture is reduced, resulting in improved composite microstructure and performance.

A continuous casting version of the planar embodiment of FIG. 2 is also possible. Same as continuous type of cylindrical embodiment Similarly, the ends of the insulated walls allow entry of the preform and withdrawal of the finished composite material. open to enable. Treatment by pulses of the material in the penetration area and The movement of material into and out of the percolation zone allows continuous casting of the composite material. It will be done.

In another example, silicon carbide particles are drilled into a cylindrical cavity in an aluminum slug. It is packed inside. This is placed inside a ceramic crucible and an aluminum The mixture is heated until it melts. Wetting between silicon carbide particles and molten aluminum Because it is weak, the metal does not naturally penetrate the particles. Next, the crucible is connected to the discharge coil. It is located in a central cavity formed by a. capacitor bank carp discharge 3KV into the cell nine times, at this point before eight more discharges are carried out. There is a pause of several hours. Metal always remains molten.

Microscopic analysis of this product shows that the particles in the composite are divided into two groups of discharges. It has been found that due to the pause between 1, the composite material is essentially homogeneous with some large pores. were only scattered throughout. More sophisticated reaction conditions, e.g. For example, given the adjusted melting temperature, number of discharges, and discharge intensity, this It is believed that large-scale porosity can be eliminated.

This experiment demonstrates that electromagnetic body forces can be used to produce virtually homogeneous composite materials. I made it clear. There are no penetration fronts in the composite material 1 produced according to this example. No mixed gas was found. A substantially homogeneous product was produced.

Preliminary work for this example shows that a substantially homogeneous metal matrix composite material has an electromagnetic volume. It has been demonstrated that it can be manufactured in a faster and more economical manner using force.

These composite materials are either cast from a crucible or cast through an opening in the bottom of the crucible. to produce an ingot with homogeneously dispersed reinforcing particles. Rukoto can. These ingots can be further processed into any desired product. I can do that.

In yet another embodiment, the carbon fiber is held together with a circumferential tow. And a 15mm diameter bundle of carbon fiber wrapped around a threaded steel loft. placed in the center of the vase. The metal was liquefied. This crucible is then used as a key for the discharge coil. It was placed in a cavity and subjected to multiple discharges. Electromagnetic body force forces this metal It was promoted and penetrated into the world.

Micrographic analysis showed that complete penetration did not occur, but more than half of the tow It turned out that the top had been penetrated. These fibers move and rotate during the discharge period. There is a strong possibility that it will not penetrate completely because it is not sufficiently suppressed.

However, under suitable conditions, virtually complete penetration is expected to occur. It will be done. The metal matrix composite material produced in this way has its maximum strength due to the fibers within the composite material. It has anisotropic properties that exist parallel to the fiber axis. parallel reinforced fiber Composite materials with can be continuously cast.

In the example described above, the body force is created by an induced magnetic field. however However, the invention is not limited to such embodiments. For example, in another embodiment, molten metal can be subjected to a separately applied electric field, for example through an electrode immersed in the metal.

If this is done while the metal is in a magnetic field, the interacting fields will cause the molten metal to Propulsive electromagnetic body force is generated.

Number of discharges Continuation of front page (72) Inventor: Andrews, Richard M. Massachusetts, USA 10, Dana Street, Cambridge, UT 02138. Nanno'C-9 (72) Inventor: Flemings, Merton Sea, Massachusetts, USA Hillside Avenue, Cambridge, TU 02139

Claims (1)

[Claims] 1. Reinforcement of substantially liquid metal in a method for the production of metal matrix composites in the step of placing the material in the vicinity of a source of inert transient magnetic field which, when activated, becomes sufficient. Therefore, the transient magnetic field and the eddy current induced in the metal by the transient magnetic field are generating electromagnetic body force within the metal through interaction; and activating said transient magnetic field, thereby causing said substantially liquid metal to move said reinforcement material; Steps to promote in the process A method characterized by comprising: 2. 2. The method of claim 1, wherein said activation step is repeated. 3. A large amount of the liquid metal and reinforcing material is continuously supplied, and the transient magnetic field including the additional step of removing the reinforcing material from which the metal is propelled. The method of claim 2, characterized in that: 4. The above metals are aluminum, nickel, cobalt, copper, beryllium, lead, tin, Contains at least one of zinc, magnesium, titanium, or iron or an alloy thereof The method according to claim 1 or 3, characterized in that: 5. Claim 1 or 3, wherein the reinforcing material includes ceramic. Law. 6. The reinforcing material may include fibers, platelets, whiskers, particles, or rods. 4. A method according to claim 1 or 3, characterized in that: 7. Claim 6 characterized in that the reinforcing material is shaped into a preform. the method of. 8. The above reinforcing materials include silicon carbide, boron, tungsten, carbon, silicon nitride, and carbon. At least one of boron oxide, silicon oxide, aluminum oxide, titanium, or steel 4. A method according to claim 1 or 3, characterized in that: 9. The propulsion step further includes subjecting the substantially liquid metal to an electric field. The method according to claim 1 or 3, characterized in that: 10. Characterized by the above transient magnetic field being generated by a discharge coil through which a current passes The method according to claim 1 or 3. 11. The frequency and attenuation constant of the repetitively activated transient magnetic field are such that the the shape of the coil, the reinforcing material, the metal, and the shape of the metal being propelled into the reinforcing material; 4. A method according to claim 3, characterized in that the method is adapted to the desired depth. 12 ．． 11. The method of claim 10, wherein said current is an oscillating current. 13. Up A transient magnetic field is generated by a discharge coil coupled to a magnetic flux concentrator through which a current passes. 4. The method according to claim 1 or 3, characterized in that: 14. Claim 13, wherein the magnetic flux concentrator contains copper or graphite. Law. 15. The penetration depth of the transient magnetic field into the reinforcing material increases depending on the thickness of the liquid metal. Therefore, it is smaller than or equal to the sum of the reinforcing material that has penetrated. 14. The method of claim 13, characterized in that they are substantially equal. 16. The current increases the penetration depth of the magnetic field into the reinforcing material to the thickness of the liquid metal. less than the sum of the parts of the reinforcing material penetrated by the metal, or greater than or approximately equal to the current required to maintain approximately equal to this Claim 15, further comprising adjusting the frequency of the current so as to the method of. 17. Current is supplied to said discharge coil by one or more capacitors. 14. The method of claim 13, characterized in that: 18. the discharge coil substantially surrounding the liquid metal and the reinforcing material; 15. The method of claim 14, wherein the method is adapted to: 19. Claim 18, wherein the discharge coil is of a solenoid type. Method. 20. Claim characterized in that the discharge coil is a substantially flat helical coil. Range 13 methods. 21. said substantially flat helical coil disposed on one side of said substantially liquid metal; and the propulsion is performed from one side thereof. Method. 22. a cooling source disposed on the other side of said substantially liquid metal; cooling the composite material after the material is propelled into the reinforcing material. Scope 21 of the methods. 23. Said substantially flat helical coils are placed on either side of said reinforcing material. 21. The method of claim 20. 24. In a method for manufacturing a metal matrix composite material, an amount of a substantially solid placing a metal in a heat-resistant container; heating said metal to substantially liquid state; , dipping a preform of reinforcing material into said metal; said metal and said supplement; The above-mentioned heat-resistant container containing strong materials should be placed near a source of inert transient magnetic fields that will become sufficient when activated. the transient magnetic field and the vortices induced in the metal by the transient magnetic field; generating an electromagnetic body force in the metal through interaction of electric currents; and activating the transient magnetic field, thereby propelling the metal into the reinforcing material; and A method characterized by comprising: 25. In a method for the production of metal matrix composites, reinforcing material is placed in a heat-resistant container. substantially surrounding said reinforcing material with a quantity of solid metal; heating said metal to a substantially liquid state; preforming reinforcing material within said metal; Activating the heat-resistant container containing the metal and the reinforcing material by immersing the The transient magnetic field and the transient An electric current is generated in the metal through the interaction of eddy currents induced in the metal by a magnetic field. generating a magnetic body force; and activating the transient magnetic field, thereby propelling the metal into the reinforcing material; and A method characterized by comprising: 26. In a method for the continuous production of metal matrix composites, substantially liquid gold is transporting the reinforcing material into the infiltration region and the liquid metal into the infiltration region; a step of conveying into the vicinity of By applying the liquid metal to a magnetic field, the liquid metal penetrates into the reinforcing material. stages, and conveying said infiltrated composite material out of said infiltration area; A method characterized by comprising: 27. The reinforcing material includes particles, fibers, whisker crystals, or rods. The method of claim 26. 28. 28. The method of claim 27, wherein the particles include silicon carbide particles. . 29. Claims characterized in that the fibers include carbon fibers. 27 methods. 30. the fibers conveyed to the entry area are uniaxially oriented and have an axial characterized in that the fibers are maintained in said uniaxial orientation during said infiltration step. 27 Methods for Scope of Requirement. 31. In an apparatus for manufacturing a metal matrix composite material using electromagnetic body force, permeation region with adjacent liquid metal and reinforcing material subregions, and activation and deactivation an electromagnetic field source adjacent to said liquid metal sub-region of said permeation region, which may be , an electromagnetic field source that generates transient magnetic fields and associated eddy currents in the metal; an electromagnetic device oriented to propel the material into the reinforcing material sub-region of the permeation region; world source A device comprising: 32. Claim 31, characterized in that said electromagnetic field source surrounds said penetration area. equipment. 33. 32. The apparatus of claim 31, wherein said electromagnetic field source includes a discharge coil. . 34. The discharge coil may include a helical coil adjacent to one side of the entry area. 34. The apparatus of claim 33, characterized in that: 35. at least one capacitor bank and said capacitor bank discharging said capacitor bank; further comprising a trigger circuit that is passed through when discharging the current through the coil. 35. The apparatus of claim 34. 36. further comprising a magnetic flux concentrator coupled to the discharge coil. The apparatus of claim 35. 37. The device of claim 36, wherein the magnetic flux concentrator comprises copper or graphite. Place. 38. A claim characterized in that the permeation region is defined by a heat-resistant crucible. Range 31 device. 39. The reinforcing material is a preform, and the crucible further contains a preform. characterized by comprising a device for moving up and down within and from the permeation region; 39. The apparatus of claim 38. 40. Said preform is placed into and above said permeation zone for raising and lowering said preform. The apparatus of claim 1 is characterized in that the device includes a bobbin centered within the crucible. Range 39 device. 41. The bobbin directs the flow of metal propelled by the electromagnetic field source into the crucible. 41. The device of claim 40, characterized in that it guides radially from a central axis. 42. The claim is characterized in that the penetration area is defined by a heat-resistant tube. Apparatus in the desired range 31. 43. further comprising a conveying device for conveying reinforcing material through the heat-resistant tube. 43. The apparatus of claim 42. 44. In an apparatus for manufacturing a metal matrix composite material using electromagnetic body force, a permeable region with adjacent liquid metal and reinforcing material sub-regions, surrounding said permeable region; a heating device, the metal being disposed within the liquid metal sub-region of the permeation region; a heating device capable of maintaining the liquid state; and an electromagnetic field source capable of activating and deactivating said liquid metal sub-layer in said permeation region; an electromagnetic field adjacent to the area that produces transient magnetic fields and associated eddy currents in the metal; a discharge coil that directs the metal into the reinforcing material sub-region of the permeation region; An apparatus characterized in that it includes an electromagnetic field source that is oriented for propulsion. 45. The heating device includes a thermostatically controlled heating element surrounding the electromagnetic field source. 45. The apparatus of claim 44.