CN212704348U

CN212704348U - Powder processing apparatus and 3D printing system

Info

Publication number: CN212704348U
Application number: CN202020654290.2U
Authority: CN
Inventors: 王山
Original assignee: China Aviation Maite Fine Metallurgical Technology Xuzhou Co ltd
Current assignee: China Aviation Maite Fine Metallurgical Technology Xuzhou Co ltd
Priority date: 2020-04-26
Filing date: 2020-04-26
Publication date: 2021-03-16
Anticipated expiration: 2030-04-26

Abstract

The utility model discloses a powder processing apparatus and 3D printing system relates to 3D and prints technical field to improve the sphericity and the mobility of powder, thereby avoid the part to form the defect when the shaping. The powder processing apparatus includes: a treatment chamber and at least one nozzle for ejecting a gas stream; the treatment cavity is provided with a powder inlet, the upper part of the treatment cavity is provided with a powder outlet, the lower part of the treatment cavity is provided with at least one air inlet, and each nozzle is arranged at the corresponding air inlet; the distance between the powder inlet and the powder outlet is smaller than that between the nozzle and the powder outlet. The utility model provides a powder processing apparatus is arranged in the 3D printing technique.

Description

Powder processing apparatus and 3D printing system

Technical Field

The utility model relates to a 3D prints technical field, especially relates to a powder processing apparatus and 3D printing system.

Background

The metal 3D printing technology is a process for quickly forming metal powder by using high-energy beams, can be suitable for processing various different metal workpieces, and has wide application prospects.

In the prior art, computer software can be used for slicing and path planning of part layering, then a high-energy beam (such as laser) is used for scanning along a preset path, metal powder is melted under the action of the high-energy beam and is rapidly cooled, solidified and formed, and then printing of a sliced layer is completed. On the basis, a layer of metal powder is laid on the cut layer again, and the next layer of printing process is continued.

However, during the atomization process, fine metal droplets float in the atomization chamber due to turbulence of the gas flow and adhere to the surface of the coarse powder particles to form metallurgical bonds, thereby forming large areas of powder agglomerates or satellite powder as shown in fig. 1. At this time, powder particles are bridged to block the powder flow, so that the powder is not uniformly spread, and the powder cannot be melted through when being melted, so that the formed part has defects.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a powder processing apparatus and 3D printing system to improve the sphericity and the mobility of powder, thereby avoid the part to form the defect when the shaping.

In order to achieve the above object, the present invention provides a powder processing apparatus, comprising: a treatment chamber and at least one nozzle for ejecting a gas stream; the treatment cavity is provided with a powder inlet, the upper part of the treatment cavity is provided with a powder outlet, the lower part of the treatment cavity is provided with at least one air inlet, and each nozzle is arranged at the corresponding air inlet; the distance between the powder inlet and the powder outlet is smaller than that between the nozzle and the powder outlet.

Optionally, an included angle formed by the spraying direction of the nozzle and the preset direction is 60-80 degrees; the preset direction is the axial direction of the bottom of the processing cavity pointing to the top.

Optionally, the nozzle is a high pressure nozzle; the high-pressure nozzle is a nozzle with the pressure of 0.2 MPa-0.6 MPa.

Optionally, the number of the nozzles is at least two; the number of the air inlets is at least two.

Preferably, at least two of the gas inlets are arranged in the circumferential direction of the treatment chamber.

Preferably, at least two air inlets are symmetrically arranged on the circumferential direction of the treatment cavity.

Preferably, at least two of the gas inlets are distributed along an axial direction of the process chamber; or the like, or, alternatively,

at least two air inlets are arranged in the circumferential direction of the treatment cavity.

Preferably, at least two air inlets are arranged in the circumferential direction of the treatment cavity in a spiral distribution mode.

Preferably, the treatment chamber is cylindrical in shape.

Compared with the prior art, the utility model provides an among the powder processing apparatus, seted up into the powder mouth on the process chamber, at least one air inlet has been seted up to the lower part of process chamber, and every nozzle is established on corresponding air inlet, and the powder mouth has been seted up on the upper portion of process chamber. Based on this, when the metal powder enters the processing chamber through the powder inlet, only the gas flow can be ejected into the processing chamber by each nozzle. And because the air inlet is opened in the lower part of handling the chamber, the distance of powder inlet and powder outlet is less than the distance of nozzle and powder outlet, consequently, the air current that at least one nozzle jetted can make metal powder violent motion in the cavity, and the chance that bumps between each metal powder increases. In the process, the powerful shearing and impact effect of the airflow is utilized, the metal powder which is agglomerated together through physical connection or electrostatic adsorption can be blown away, and the small-particle satellite powder adhered to the surface of the large powder particles is sheared, so that bridging between the metal powder is avoided, the sphericity and the flowability of the metal powder are improved, and the powder paving state is better. Meanwhile, due to the fact that the bridging phenomenon among the metal powder is avoided, the metal powder can be in full contact with each other, powder particles can be fully melted through when laser scanning is conducted, and the defect of forming of parts during printing and forming can be avoided.

The utility model also provides a 3D printing system, including above-mentioned powder processing apparatus.

Compared with the prior art, the utility model provides a 3D printing system's beneficial effect is the same with the beneficial effect of the powder processing apparatus that above-mentioned technical scheme provided, and the here is not repeated.

Drawings

The accompanying drawings, which are included to provide a further understanding of the invention and are incorporated in and constitute a part of this specification, illustrate embodiments of the invention and together with the description serve to explain the invention without undue limitation to the invention. In the drawings:

FIG. 1 is an electron microscope image of a metal powder morphology in the prior art;

fig. 2 is a schematic structural diagram of a powder processing apparatus according to an embodiment of the present invention;

fig. 3 is an electron microscope image of the morphology of the metal powder after being processed by the powder processing apparatus provided by the embodiment of the present invention;

fig. 4 is a schematic top view of a nozzle distribution according to an embodiment of the present invention;

fig. 5 is a schematic top view of another nozzle distribution according to an embodiment of the present invention.

Reference numerals:

1-powder inlet, 2-air inlet, 3-nozzle, 4-treatment cavity and 5-powder outlet.

Detailed Description

In order to make the technical problem, technical solution and advantageous effects to be solved by the present invention more clearly understood, the following description is given in conjunction with the accompanying drawings and embodiments to illustrate the present invention in further detail. It should be understood that the specific embodiments described herein are for purposes of illustration only and are not intended to limit the invention.

It will be understood that when an element is referred to as being "secured to" or "disposed on" another element, it can be directly on the other element or be indirectly on the other element. When an element is referred to as being "connected to" another element, it can be directly connected to the other element or be indirectly connected to the other element.

Furthermore, the terms "first", "second" and "first" are used for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include one or more of that feature. In the description of the present invention, "a plurality" means two or more unless specifically limited otherwise. The meaning of "a number" is one or more unless specifically limited otherwise.

In the description of the present invention, it is to be understood that the terms "upper", "lower", "front", "rear", "left", "right", and the like indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience of description and simplification of description, but do not indicate or imply that the device or element referred to must have a specific orientation, be constructed in a specific orientation, and be operated, and thus, should not be construed as limiting the present invention.

In the description of the present invention, it is to be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; either directly or indirectly through intervening media, either internally or in any other relationship. The specific meaning of the above terms in the present invention can be understood according to specific situations by those skilled in the art.

As shown in fig. 2, an embodiment of the present invention provides a powder processing apparatus. The powder processing apparatus includes: a treatment chamber 4 and at least one nozzle 3 for ejecting a gas flow. The processing cavity 4 is provided with a powder inlet 1. The upper part of the processing cavity 4 is provided with a powder outlet 5. At least one air inlet 2 is arranged at the lower part of the processing cavity 4. Each nozzle 3 is provided at a respective air inlet 2. The distance between the powder inlet 1 and the powder outlet 5 is less than the distance between the nozzle 3 and the powder outlet 5.

The processing chamber is a reaction chamber of the powder processing device and comprises an outer wall with an upper opening and a closed bottom, and a space is arranged in the chamber and can process and contain the entering metal powder.

The powder inlet is used for providing metal powder for the processing cavity. The metal powder may enter the process chamber from the powder inlet along with the gas flow. The gas stream may be a stable gas, such as: argon, nitrogen, or a mixture of the two, but not limited thereto.

The gas inlet is used for conveying processing gas for processing the metal powder, and the nozzle is arranged at the gas inlet and used for spraying gas flow to the interior of the processing cavity. The gas flow may be a steady gas, such as: argon, nitrogen, or a mixture of the two, but not limited thereto.

The powder outlet is used for providing a powder outlet channel. It can be understood that the metal powder in the processing chamber can be blown out of the processing chamber through the powder outlet by the airflow to enter the next process.

The distance between the powder inlet and the powder outlet is smaller than the distance between the nozzle and the powder outlet. At the moment, the position of the powder inlet is higher than the height of the nozzle, so that the metal powder can be impacted by the airflow jetted by the nozzle from the bottom of the processing cavity to the top of the processing cavity and directly discharged out of the processing cavity from the powder outlet.

In order to understand the powder processing process of the powder processing apparatus provided by the embodiment of the present invention, two nozzles are briefly described below as an example. As shown in fig. 2, the powder inlet 1 is arranged on the upper portion of the side wall of the processing chamber 4, the two air inlets 2 are symmetrically arranged on the lower portion of the side wall of the processing chamber 4, the nozzle 3 is located at the air inlet 2, the powder outlet 5 is arranged on the top of the processing chamber 4, and the powder inlet 1 is located on the upper portion of the nozzle 3, namely, the position of the powder inlet 1 is higher than the height of the nozzle 3.

Specifically, the metal powder enters the processing chamber through a powder inlet along with a gas flow (such as argon), and the nozzle sprays the gas flow into the processing chamber. At this time, the air current jetted from the nozzle can process the metal powder in the processing cavity, and the processed metal powder can be discharged from the powder outlet and subjected to subsequent powder laying operation.

For example: 5kg of titanium alloy TC4 powder is taken, the sphericity of the metal powder is detected to be 0.85 before treatment, and the Hall flow rate is zero. Send into titanium alloy TC4 powder through advancing the powder mouth the embodiment of the utility model provides an among the powder processing apparatus to utilize the nozzle to let in inert gas argon gas to the treatment chamber, argon gas purity is 99.999%, and the admission pressure of adjustment nozzle is 0.3Mpa, and the angle of adjustment nozzle and predetermined direction is 65, and the processing time of metal powder in the treatment chamber is 10 min. After the treatment, the metal powder discharged from the powder outlet was taken out, and the sphericity was detected to be 0.92 and the Hall flow rate was 32s/50 g. Therefore, titanium alloy TC4 powder is through the utility model provides a powder processing apparatus handles the back, and its sphericity is improved to 0.92 by 0.85, and its velocity of flow increases to 32s/50g by zero, so this metal powder's sphericity and mobility all improve to some extent, and this has reflected the utility model provides a powder processing apparatus can realize its beneficial effect.

Another example is: 10kg of nickel-based superalloy GH4169 powder is taken, the sphericity of the metal powder is detected to be 0.87 before treatment, and the Hall flow rate is 18s/50 g. Send into this metal powder through advancing the powder mouth the embodiment of the utility model provides an among the powder processing apparatus to utilize the nozzle to let in the inert gas argon gas to the treatment chamber, the purity of argon gas is 99.999%, and the admission pressure of adjustment nozzle is 0.5Mpa, and the angle of adjustment nozzle and preset direction is 75, and the processing time of metal powder in the treatment chamber is 15 min. After the completion of the treatment, the metal powder discharged from the powder outlet was taken out, and the sphericity thereof was examined to be 0.93 and the Hall flow rate was 13s/50 g. Therefore, after the powder processing device provided by the embodiment of the utility model processes the nickel-based superalloy GH4169 powder, the sphericity thereof is improved to 0.93 by 0.87, and the Hall flow rate thereof is slightly reduced, so when the mobility of the metal powder is not changed greatly, the sphericity of the metal powder is improved more, which can also illustrate that the powder processing device provided by the embodiment of the utility model can realize the beneficial effects thereof.

The utility model provides an among the powder processing apparatus, when metal powder got into the process chamber through advancing the powder mouth, as long as guarantee that each nozzle can erupt the air current in to the process chamber. And because the air inlet is seted up in the lower part of treatment chamber, the distance of advancing powder mouth and powder outlet is less than the distance of nozzle and powder outlet, consequently, the air current that at least one nozzle jetted can make metal powder move the aggravation in the cavity, and the chance of bumping between each metal powder increases. In the process, by utilizing the powerful shearing and impact action of the airflow, as shown in fig. 3, the metal powder which is agglomerated together through physical connection or electrostatic adsorption can be blown away, and the small-particle satellite powder adhered to the surface of the large powder particle is sheared off, so that bridging among the metal powder is avoided, the sphericity and the fluidity of the metal powder are improved, and the powder spreading state is better. Meanwhile, due to the fact that the bridging phenomenon among the metal powder is avoided, the metal powder can be in full contact with each other, the metal powder can be fully melted through when laser scanning is conducted, and the defect of forming of parts during printing and forming can be avoided.

It should be noted that the shape of the processing chamber may be various, for example: as shown in fig. 2, the process chamber 4 may be cylindrical. This is mainly because the cylindrical processing chamber 4 can store more reaction materials or processing gases, and can make the distribution of the metal powder and the gas flow in the processing chamber 4 more uniform, and the space volume occupied by the cylindrical processing chamber is minimized, and the energy loss during the reaction can be reduced. Therefore, in the cylindrical treatment cavity 4, the metal powder which can be treated at the same time has more volume, good treatment effect, cost saving and convenient transportation.

As a possible implementation manner, as shown in fig. 2, the spraying direction of the nozzle 3 has an included angle with the preset direction, and when the included angle is 60 ° to 80 °, the processing effect of the gas flow on the metal powder is optimal. It should be noted that the preset direction is an axial direction in which the bottom of the process chamber 4 is directed to the top.

For example, as shown in fig. 2, when the included angle between the spraying direction of the nozzle 3 and the preset direction is 60 ° to 80 °, the metal powder enters the processing chamber 4, and the nozzle 3 with a certain inclination angle sprays the gas flow with a corresponding inclination angle. When this air current sweeps metal powder, the air current passes through metal powder, blows to the lateral wall of process chamber 4, has guaranteed like this that the air current is to metal powder's processing time and throughput, also can avoid causing direct impact to metal powder, directly blows out powder outlet 5 with metal powder. It should be understood that the specific angle of the nozzle 3 can be adjusted according to the material type, the treatment effect and the treatment efficiency to be achieved, so that the purging effect is optimal.

As one possible implementation, as shown in fig. 2, 4 or 5, the nozzle 3 may be a high-pressure nozzle 3, and the high-pressure nozzle 3 may be a nozzle 3 having a pressure of 0.2MPa to 0.6 MPa. The pressure of the gas flow ejected from the nozzle 3 can be maintained at 0.2 to 0.6MPa by adjusting the pressure of the gas supplied from the gas inlet 2. It should be noted that when the pressure is too low (for example, when the pressure is less than 0.2MPa), the gas pressure of the gas flow is too low, and the effect of improving the morphology of the powder is poor. If the pressure is too high (for example, a pressure greater than 0.6MPa), the powder may be deformed by the too high pressure, which may affect the sphericity thereof. It should be understood that the high-pressure nozzle is an existing nozzle, and the pressure of the nozzle is adjusted within a proper range through a certain pressure adjusting mode without additional modification.

Illustratively, when the pressure of the nozzle is controlled to be 0.2 MPa-0.6 MPa, at this time, as shown in fig. 2, 4 or 5, the nozzle 3 can eject airflow with certain pressure and speed, the airflow with high pressure and high speed can generate certain impact force on the metal powder in the processing chamber 4, and through the strong shearing and impact action of the airflow, the metal powder agglomerated together in the processing chamber 4 can be blown away, and meanwhile, the small-particle satellite powder adhered to the surface of the large-particle powder is sheared off, so that bridging between the metal powder is avoided, and further, the sphericity and the fluidity of the metal powder are improved.

As a possible realization, the number of the above-mentioned air inlets 2 is at least two, as shown in fig. 2. It should be understood that the gas inlet 2 may be fixedly connected to the process chamber 4 or may be mechanically connected thereto, which is not required here. At least two air inlets 2 provide multiple streams of air, as opposed to one air inlet 2, and the multiple streams are emitted through nozzles 3 in various orientations. The multiple air flows can be fully contacted with the metal powder at different corners in the processing cavity 4, so that the metal powder can be processed better.

Whereas each nozzle is provided with a respective air inlet, the position of the air inlet determines the position of the nozzle. On this basis, if the number of air inlets is at least two, the number of nozzles is likewise at least two. When the number of the air inlets is at least two, the positions of the air inlets can be regulated to configure the distribution positions of the nozzles.

In an alternative, as shown in fig. 2, the at least two gas inlets 2 are arranged in the circumferential direction of the process chamber 4. At least two gas inlets 2 located circumferentially around the process chamber 4 may provide multiple gas streams in multiple directions, which are ejected through at least two nozzles 3. The multi-strand airflow in multiple directions can sweep different angles of the metal powder which is agglomerated together from multiple directions simultaneously, so that the treatment effect is improved. It should be understood that the at least two gas inlets 2 may be uniformly arranged in the circumferential direction of the process chamber 4, or may be non-uniformly arranged in the circumferential direction of the process chamber. When the at least two gas inlets 2 are non-uniformly arranged in the circumferential direction of the processing chamber 4, the multiple gas flows ejected from the at least two nozzles 3 may have non-uniform phenomena (e.g., overlapping or crossing of the multiple gas flows), which may cause non-uniform impact of the gas flows on the metal powder, resulting in deformation of the morphology of the metal powder.

For example, as shown in fig. 4, the at least two gas inlets 2 may be symmetrically disposed in the circumferential direction of the process chamber 4. The symmetry sets up and can avoid taking place to overlap or intersect between the stranded air current at 4 two at least air inlets 2 of circumference of process chamber to avoid the asymmetric air current of stranded to cause inhomogeneous impact to metal powder, can make metal powder's atress relatively balanced, can make the stress point of powder be located the central axis of meal outlet like this, the powder granule that has been handled like this can be easily along with the air current direction is discharged from meal outlet. To some extent, the air inlets 2 symmetrically arranged in the circumferential direction of the processing chamber 4 may promote the processing effect of the air flow on the powder particles.

As shown in fig. 4, when the number of the gas inlets 2 is two, and the two gas inlets 2 are distributed in the circumferential direction of the processing chamber 4 in an axisymmetric manner, the included angle between the two nozzles 3 located in the two gas inlets 2 and the preset direction is 60 ° to 80 °. At this time, the two air flows jetted by the nozzle 3 converge and intersect at the central axis position of the processing cavity 4, and it can be considered that one air flow impacts the left side of the metal powder, and the other air flow impacts the right side of the same metal powder, so that the two air flows uniformly impact the metal powder, and the stress of the metal powder is balanced. At the moment, the two air flows have strong shearing and impact effects on the metal powder, so that the agglomerated metal powder can be blown away, and meanwhile, the small-particle satellite powder adhered to the surfaces of the large powder particles is sheared, so that bridging between the metal powder is avoided, and the sphericity and the flowability of the metal powder are improved.

As shown in fig. 5, when the number of the gas inlets 2 is three, and the three gas inlets 2 are distributed in the circumferential direction of the processing chamber 4 in a central symmetrical manner, the included angles between the three nozzles 3 located at the three gas inlets 2 and the preset direction are 60 ° to 80 °. At this time, the three nozzles 3 are distributed in the circumferential direction of the treatment chamber 4 in the form of an equilateral triangle in plan view, with the center points thereof located on the center axis of the treatment chamber 4. At this time, the three air flows jetted by the nozzle 3 converge and intersect at the central axis of the processing chamber 4, and the included angles formed between any two air flows in the three air flows are all 60 °, so that the three air flows form uniform impact on the metal powder, that is, the stress of the metal powder is balanced. At the moment, the three air flows have strong shearing and impact effects on the metal powder, so that the metal powder which is agglomerated together can be blown away, and meanwhile, the small-particle satellite powder adhered to the surface of the large powder particles is sheared, so that bridging between the metal powder is avoided, and the sphericity and the flowability of the metal powder are improved.

In another alternative, the at least two gas inlets may be formed at the same height of the processing chamber, or may be formed at different heights of the processing chamber. When the at least two air inlets are arranged at different heights of the processing cavity, the at least two air inlets are distributed along the axial direction of the side wall of the processing cavity. At this time, the gas inlets distributed along the axial direction of the sidewall of the process chamber can generate gas flows in a plurality of directions from the bottom of the process chamber to the middle of the process chamber, and the throughput and the processing efficiency of the powder in the process chamber can be further increased.

For example, the at least two gas inlets may be arranged in a spiral distribution manner on the circumference of the sidewall of the processing chamber. Establish at two at least air inlets of process chamber lateral wall circumference and the radial direction of process chamber with the spiral distribution mode and form certain angle, can all carry out gas to upper portion from the lower part of process chamber, the air inlet of staggering the distribution can provide the gas of a plurality of directions and then spout the air current of a plurality of directions through a plurality of nozzles, these air currents make metal powder form the vortex form in the inside of process chamber and distribute, and direct convection current of non-strikes, can prevent that the air current from striking the inner wall that destroys the process chamber, the air inlet and the nozzle of spiral distribution mode can make gas distribution even in the process chamber simultaneously, and produce the ascending traction force from the directional top in process chamber bottom, can strengthen the diversified impact force to metal powder, the process of blowing out the process chamber with metal powder has also been accelerated.

The utility model also provides a 3D printing system. The 3D printing system comprises the powder processing device. The beneficial effect of this 3D printing system is the same with the beneficial effect of the powder processing apparatus that above-mentioned technical scheme provided, and this is not repeated here.

In the foregoing description of embodiments, the particular features, structures, materials, or characteristics may be combined in any suitable manner in any one or more embodiments or examples.

The above description is only for the specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any person skilled in the art can easily think of the changes or substitutions within the technical scope of the present invention, and all should be covered within the protection scope of the present invention. Therefore, the protection scope of the present invention shall be subject to the protection scope of the claims.

Claims

1. A powder processing apparatus, comprising: a treatment chamber and at least one nozzle for ejecting a gas stream; the treatment cavity is provided with a powder inlet, the upper part of the treatment cavity is provided with a powder outlet, the lower part of the treatment cavity is provided with at least one air inlet, and each nozzle is arranged at the corresponding air inlet; the distance between the powder inlet and the powder outlet is smaller than that between the nozzle and the powder outlet.

2. The powder treatment apparatus according to claim 1, wherein the spray direction of the nozzle forms an angle of 60 ° to 80 ° with the preset direction; the preset direction is the axial direction of the bottom of the processing cavity pointing to the top.

3. The powder processing apparatus of claim 1, wherein the nozzle is a high pressure nozzle;

the high-pressure nozzle is a nozzle with the pressure of 0.2 MPa-0.6 MPa.

4. The powder processing apparatus according to claim 1, wherein the number of the nozzles is at least two; the number of the air inlets is at least two.

5. The powder processing apparatus of claim 4, wherein at least two of the inlet ports are provided in a circumferential direction of the processing chamber.

6. The powder processing apparatus of claim 4, wherein at least two of the gas inlets are symmetrically disposed about a circumference of the processing chamber.

7. The powder processing apparatus according to claim 4, wherein at least two of the gas inlets are distributed along an axial direction of the processing chamber; or the like, or, alternatively,

8. The powder processing apparatus of claim 4, wherein at least two of the inlet ports are arranged in a spiral distribution around the circumference of the processing chamber.

9. The powder treatment apparatus according to any one of claims 1 to 8, wherein the treatment chamber has a cylindrical shape.

10. A 3D printing system comprising the powder handling apparatus of any one of claims 1 to 9.