System for space heterostructure material additive manufacturing

Abstract

The invention provides a system for space heterostructure material additive manufacturing, and aims to solve the problems of heterogeneous powder pollution and recovery, space heterostructure deposition workpiece precision optimization, defect control and the like in the prior art. The system comprises a device shell, a heterogeneous powder feeding and recycling device, an additive rolling cooperation platform, an ultrasonic vibration clamping platform and a powder screening and collecting device. The heterogeneous powder feeding and recycling device controls a rotating round block and a tapping sliding block to move through a servo driving mechanism to achieve switching and recycling of heterogeneous powder and cleaning work of a powder feeding path. The material adding and rolling cooperation platform integrates a 3D material adding mechanism, a powder cleaning mechanism and a rolling mechanism, the angle of a nozzle is adjusted by driving a bevel gear transmission assembly, cleaning of residual powder on the deposition surface under different defocusing amounts is achieved, and the material adding and rolling cooperation platform cooperates with the rolling mechanism to flatten the deposition surface. The ultrasonic vibration clamping platform improves the deposition quality of the laser directed energy deposition (LDED) spatial heterostructure through precise clamping and ultrasonic vibration.

Description

Technical Field

[0001] The present invention relates to the field of laser additive manufacturing, and particularly to a system for additive manufacturing of spatially heterogeneous structure materials. Background Art

[0002] Laser directed energy deposition (LDED) technology is an important branch of additive manufacturing, with functions of component manufacturing and repair, and is widely used in fields such as aerospace, medical, and mold manufacturing. Traditional LDED still faces some technical bottlenecks when manufacturing complex heterogeneous structure materials (such as spatially heterogeneous structure materials). Specifically, spatially heterogeneous structure materials refer to materials that achieve spatial grading of material properties through specific additive manufacturing processes and utilize the distribution characteristics of different materials in the same structure. Their material properties, tissue structures, and chemical compositions show spatial variations in different regions. This structural design allows the material to meet complex multi-functional requirements while maintaining the coordinated improvement of light weight and high plasticity. However, due to the need to alternately use multiple metal powders (such as nickel-based superalloys, titanium alloys, high-entropy alloys, iron-based alloys, etc.) during the deposition process of heterogeneous materials and the adoption of special additive paths, problems such as powder feeding path contamination, difficulty in recycling different powders, increased hole defects in the workpiece, and decreased accuracy often occur. Summary of the Invention

[0003] Based on the above background, the present invention aims to systematically solve the problems of powder contamination, surface flatness, hole defects, and waste powder recycling in the additive manufacturing of heterogeneous structure materials by designing a laser additive manufacturing system for spatially heterogeneous structure materials, which includes a heterogeneous powder feeding and recycling device, an additive roll pressing collaborative platform, an ultrasonic vibration clamping platform, and a waste powder screening and collection device. This device can not only achieve the manufacturing of high-quality heterogeneous structure materials, but also adapt to conventional additive manufacturing and various additive processes (such as ultrasonic-assisted, roll pressing additive, etc.).

[0004] To achieve the above object, the technical solution adopted by the present invention is as follows:

[0005] The present invention provides a system for additive manufacturing of spatially heterogeneous structural materials, including a heterogeneous powder feeding and recycling device, an additive rolling collaborative platform, an ultrasonic vibration clamping platform, and a powder screening and collection device; the heterogeneous powder feeding and recycling device includes a lower base plate, a disc seat, a rotating disc block, a disc, and a cover plate; above the cover plate, there are multiple powder feeding nozzles and an air inlet nozzle, the cover plate is fixedly connected to the disc below, and both the disc and the cover plate are provided with air transmission channels and powder feeding channels that are closely connected up and down. The air transmission channel is located at the center of the disc and communicates with the air inlet nozzle on the upper side, and the upper side of the powder feeding channel communicates with the powder feeding nozzle. The lower part of the disc is a rotating disc block, which is connected to a rotating drive device. A through groove is opened along a radius direction on the rotating disc block, and an opening slider is arranged in the through groove. A hole is opened on the opening slider, and the opening slider is connected to a linear drive device. The lower side of the rotating disc block is connected to the disc seat through an annular guide rail slider mechanism, and the disc seat is fixedly connected to the lower base plate. The disc seat and the lower base plate are provided with corresponding central channels and powder recovery pipelines at the same vertical positions of the four holes of the disc. The lower part of the central channel is connected to a powder feeding pipe, and the other end of the powder feeding pipe is connected to a laser head. The remaining powder recovery pipelines are connected to a collection box through pipelines; the additive rolling collaborative platform is arranged below the heterogeneous powder feeding and recycling device, the ultrasonic vibration clamping platform is arranged below the additive rolling collaborative platform, and the powder screening and collection device is located below the ultrasonic vibration clamping platform.

[0006] As a further technical solution, the additive rolling platform is composed of a 3D additive manufacturing mechanism, a powder cleaning mechanism, and a rolling mechanism. The 3D additive manufacturing mechanism includes a first rectangular frame, which is connected to the inner wall of the middle section of the dust-proof housing through a slider guide rail mechanism on the outer side of the first rectangular frame, and the first rectangular frame realizes its up and down movement through a Z-direction drive mechanism; a second rectangular frame is installed on the inner side surface of the first rectangular frame, and the second rectangular frame is driven by a Y-direction drive mechanism to move along the Y direction inside the first rectangular frame. An installation frame is carried on the second rectangular frame, and a laser head is installed on the installation frame. The laser head installation frame moves along the X direction under the drive of an X-direction drive mechanism; a powder cleaning mechanism and a rolling mechanism are installed at the bottom of the first rectangular frame.

[0007] As a further technical solution, the powder cleaning mechanism includes a rotating rod and a jet component. Four rotating rods are installed below the first rectangular frame through multiple bearing seats. The bearing seats are fixedly connected to the lower side of the first rectangular frame. The four rotating rods pass through the bearing seats and are connected by four groups of bevel gear sets. The bevel gear sets can make the four rotating rods rotate synchronously by the same angle, and a jet component is installed on the rotating rod.

[0008] As a further technical solution, the jet assembly consists of an air pipe, a sealed shell, an annular airbag and a nozzle. The air pipe is located below the first circular frame. The first circular frame has an air duct communicating therewith. An air inlet port is installed above the air duct of the first circular frame. The air inlet port is connected to the inert gas pipeline. A sealed shell is fixedly connected below the air pipe. The sealed shell and the annular airbag can rotate with each other. A closed cavity can be formed between the annular airbag and the sealed shell. The annular airbag is fixedly connected to the transmission rod, and a conical nozzle is provided on the annular airbag.

[0009] As a further technical solution, the rolling mechanism includes a servo cylinder, a core shaft and a rolling roller; a slide groove is symmetrically opened on the lower side of the long side of the first circular frame, a slider is matched in the slide groove, a servo cylinder is fixedly connected below the slider, a bearing seat is connected to the lower end of the servo cylinder, the bearing seat is used to install the core shaft, and the outer side of the core shaft is the rolling roller; and a distance measuring sensor is arranged below the first circular frame.

[0010] As a further technical solution, the ultrasonic vibration clamping platform is composed of a slider hinge mechanism, a support rod, a powder blocking mechanism, a mobile clamping platform and an ultrasonic vibration platform. The two ends of the support rod are placed in a rectangular hole that passes through the dustproof shell on the same horizontal plane. A slide plate is installed in the rectangular hole and is mounted on the support rod. The slide plate is embedded in a slide rail provided in the middle layer of the dustproof shell. The size of the slide plate is larger than the size of the rectangular hole. A slider hinge mechanism is fixedly connected to one end of the support rod on the outside of the dustproof shell; a powder blocking mechanism is also provided on the support rod inside the dustproof shell; a mobile clamping platform is fixedly installed on the middle section of the support rod; and an ultrasonic vibration mechanism is also carried in the middle of the mobile clamping platform.

[0011] As a further technical solution, the slider hinge mechanism includes a horizontal slider, which is placed in a limiting slide groove and hinged with a connecting rod. The other end of the connecting rod is connected to a vertical slider through a hinge. The vertical slider is sleeved on a guide slide rod, and the guide slide rod is fixed on a slide rod seat and a slide rod bracket. The slide rod seat and the slide rod bracket are fixedly connected to the outer wall of the dustproof shell.

[0012] As a further technical solution, the powder blocking mechanism is composed of a powder blocking plate, a clockwork spring and a Teflon film. The blocking plate is sleeved on the support rod and can slide relatively manually. The Teflon film is connected to the clockwork spring.

[0013] As a further technical solution, the powder screening and collection device is composed of a heterogeneous powder collection box and a waste powder conveying and screening mechanism. The waste powder conveying and screening mechanism is composed of a partition board, a conveyor belt, a movable funnel, a funnel driving assembly, a powder screening mechanism, a powder screening driving assembly and a support frame. The partition board is installed between the cover plate and the conveyor belt support frame. A closing baffle is integrally connected above the tail end of the conveyor belt. A scraper is arranged between the tail end of the conveyor belt and the movable funnel. The movable funnel can be driven by the funnel driving assembly to move along a chute processed on the support plate. An outlet is processed at the bottom of the movable funnel, and the additive manufacturing waste powder is conveyed to the powder screening mechanism through the outlet.

[0014] As a further technical solution, the powder screening mechanism is composed of a powder baffle, a coarse particle powder collection box, a fine particle powder collection box, universal rolling balls and an inclined panel. The inclined panel is divided into three parts by the powder baffle, corresponding to different material waste powder screening areas respectively. Fine sieve holes are processed on the upper half surface of the inclined panel. A fine particle powder collection box is installed below the inclined panel with fine sieve holes. Coarse sieve holes are processed on the lower half surface of the inclined panel. A coarse particle powder collection box is installed below the inclined panel with coarse sieve holes. Universal rolling balls are movably connected below the powder collection box to support the powder collection box. The universal rolling balls are embedded in hemispherical holes with appropriate sizes processed on the bottom plate of the waste powder collection device housing. The powder screening mechanism realizes the powder screening function through the reciprocating drive of the powder screening driving assembly.

[0015] The beneficial effects of the present invention are as follows;

[0016] The laser additive manufacturing heterogeneous structure material device proposed by the present invention includes a heterogeneous powder feeding and recycling device, an additive rolling cooperation platform, an ultrasonic vibration clamping platform and a waste powder screening and collection device. Among them, the heterogeneous powder feeding and recycling device controls the movement of the rotating block and the perforated slider through the servo drive mechanism to realize the switching of heterogeneous powder, recycling and the cleaning of the powder feeding path. The additive rolling cooperation platform integrates a 3D additive mechanism, a powder cleaning mechanism and a rolling mechanism, and adjusts the nozzle angle through the driving bevel gear transmission assembly to realize the cleaning of residual powder on the deposition surface under different defocus amounts, and cooperates with the rolling mechanism to flatten the deposition surface. The ultrasonic vibration clamping platform improves the deposition quality of the laser directed energy deposition (LDED) spatial heterogeneous structure through precise clamping and ultrasonic vibration, reduces powder residue and promotes grain refinement and compositional uniformity. The powder screening and collection device realizes the classified recycling of heterogeneous powder, classifies the powder by type and particle size through the movable funnel and the powder screening mechanism, and optimizes the powder management in the LDED process.

[0017] The heterogeneous powder feeding and recycling device can effectively blow out the powder remaining in the powder feeding pipe and the laser head, avoiding subsequent pollution problems. At the same time, the heterogeneous powder remaining in the powder feeding pipe can be recycled into the heterogeneous powder collection box for reuse, improving the powder utilization rate.

[0018] The powder cleaning mechanism in the additive roll pressing collaborative platform reduces the powder remaining on the surface of the deposition layer, and also helps with the screening and recycling of subsequent heterogeneous waste powder. The various component devices of this apparatus can achieve collaborative cooperation between functions; the roll pressing mechanism in the additive roll pressing collaborative platform rolls and presses the upper surface of the deposition layer.

[0019] When the ultrasonic vibration clamping platform is used for LDED of space heterogeneous structure materials, the powder blown out from the grooves on the surface of the deposition layer by the powder cleaning mechanism and other unused powder blown out by the laser head will be blocked by the powder blocking mechanism and fall onto the conveyor belt below, which will help with the screening and recycling of the powder; the mobile clamping platform can clamp additive substrates of different sizes; the ultrasonic vibration mechanism contacts the additive substrate, further transmitting ultrasonic vibration to the additive substrate. Using ultrasonic vibration and cavitation effects, the solidified tissue grains of the space heterogeneous structure material are refined and the composition is made uniform, reducing pore defects.

[0020] The waste powder screening and collection device can achieve the screening and collection of powder.

[0021] The present invention systematically solves the problems of powder pollution, surface flatness, pore defects, and waste powder recycling in the additive manufacturing of heterogeneous structure materials. This apparatus can not only achieve the manufacturing of high-quality heterogeneous structure materials, but also adapt to conventional additive manufacturing and various additive processes (such as ultrasonic assistance, roll pressing additive manufacturing, etc.). Description of the Drawings

[0022] Figure 1 It is a schematic diagram of the overall device for laser additive manufacturing of heterogeneous structure materials;

[0023] Figure 2 It is a partial schematic diagram of the heterogeneous powder feeding and recycling device;

[0024] Figure 3 It is a schematic diagram of the middle rotating circular block of the heterogeneous powder feeding and recycling device;

[0025] Figure 4 It is a half-sectional view of the heterogeneous powder feeding and recycling device;

[0026] Figure 5 It is a top view of the additive roll pressing collaborative platform;

[0027] Figure 6 It is a bottom view of the additive roll pressing collaborative platform;

[0028] Figure 7 It is a partial schematic diagram of the jet component;

[0029] Figure 8 It is a schematic diagram of the path of laser additive heterogeneous structure materials;

[0030] Figure 9 It is a schematic diagram of the ultrasonic vibration clamping platform;

[0031] Figure 10 It is a partially enlarged view of the slider hinge mechanism;

[0032] Figure 11 It is a partially enlarged view of the ultrasonic vibration clamping platform;

[0033] Figure 12 It is a half-sectional view of the ultrasonic vibration clamping platform;

[0034] Figure 13 It is a top view of the waste powder screening and collection device;

[0035] Figure 14 It is a half-sectional view of the waste powder screening and collection device;

[0036] Figure 15 It is a partially enlarged view of the powder screening mechanism;

[0037] Figure 16 It is a partially enlarged view of the drive mechanism;

[0038] Figure 17 It is a schematic diagram of the relative positions of the laser additive manufacturing heterogeneous structure system.

[0039] In the figure: 1. Device housing; 11. Waste powder screening and collection device housing; 111. First pull-out door; 1111. First pull handle; 1112. Fixed card slot; 112. Cover plate; 113. Second pull-out door; 1131. Second pull handle; 12. Dust-proof housing; 13. L-shaped cabinet door; 131. Handle; 132. Door hinge; 14. Cover plate; 2. Heterogeneous powder feeding and recycling device; 21. Powder feeding pipe; 22. Lower bottom plate; 23. Disc seat; 231. Central hole; 232. First powder recovery hole; 24. Rotating disc; 241. Open-hole slider; 2411. Hole; 242. Servo push rod; 25. Disc; 26. Cover plate; 261. First powder feeding port; 262. Second powder feeding port; 263. Third powder feeding port; 264. Air inlet port; 265. Air transmission hole; 266. First powder feeding hole; 27. Servo motor; 271. Output shaft; 272. Gear; 273. Arc rack; 3. Additive roll pressing collaborative platform; 31. 3D additive mechanism (first looped frame); 311. Slide block; 312. Limit guide rail; 313. Slide block self-locking screw; 314. Z-direction driving mechanism; 3141. Servo motor; 3142. Coupling; 3143. Lead screw; 3144. Guide rod; 3145. T-nut seat; 315. Bladder; 316. Second looped frame; 317. Mounting frame; 318. Laser head; 32. Powder cleaning mechanism; 321. Air inlet port; 322. Labor-saving handle; 323. Rotating rod; 324. Bevel gear set; 325. Bearing seat; 326. Jet component; 3261. Air transmission pipe; 3262. Sealed housing; 3263. Annular airbag; 3264. Nozzle; 33. Roll pressing mechanism; 331. Servo cylinder; 332. Core shaft; 333. Roll; 334. Slide groove; 4. Ultrasonic vibration clamping platform; 41. Slide block hinge mechanism; 411. Limit slide groove; 412. Horizontal slide block; 413. Slide plate; 414. Slide rod seat; 415. Link; 416. Guide slide rod; 417. Hinge; 418. Vertical slide block; 419. Slide rod support; 42. Support rod; 43. Powder blocking mechanism; 431. Powder blocking plate; 432. Hairspring; 433. Teflon film; 44. Moving clamping platform; 441. First clamping component; 4411. First claw; 4412. First adjustment knob; 442. Second clamping component; 4421. Second claw; 4422. Anti-slip groove; 4423. Second claw slide plate; 4424. Second adjustment knob; 45. Telescopic mechanism; 451. Folding frame; 452. Slide block; 4521. Slide groove; 453. Rotating shaft; 454. Telescopic rod; 455. Spring; 46. Servo double-rod hydraulic cylinder; 461. Riding buckle; 47. Ultrasonic vibration mechanism; 471. Ultrasonic transducer; 472. Support plate; 473. Support table; 474. Vibration damping pedestal; 475. Ultrasonic vibration platform; 5. Powder screening and collection device; 51. Heterogeneous powder collection box; 52. Waste powder transmission and screening mechanism; 521. Partition board;5211, closing baffle; 522, conveyor belt; 523, movable hopper; 5231, powder outlet; 5232, support plate; 5233, chute; 524, hopper drive assembly; 5241, motor base; 5242, servo motor; 5243, gear; 5244, straight rack; 525, powder screening mechanism; 5251, powder baffle; 5252, coarse sieve holes; 5253, coarse particle powder collection box; 5254, fine sieve holes; 5255, fine particle powder collection box; 5256, universal rolling ball; 5257, inclined panel; 526, powder screening drive assembly; 5261, motor base; 5262, servo motor; 5263, eccentric wheel; 5264, disc; 5265, transmission rod; 5266, spring; 5267, support plate; 5268, support spring; 5269, reciprocating block; 527, support frame; 6, hole defect. Detailed implementation manners

[0040] In order to better understand the technical content of the present invention, specific embodiments are hereby given and described in conjunction with the accompanying drawings as follows.

[0041] In the present disclosure, aspects of the present invention are described with reference to the accompanying drawings, in which many illustrative embodiments are shown. The embodiments of the present disclosure are not necessarily intended to cover all aspects of the present invention. It should be understood that the various concepts and embodiments introduced above, as well as those described in more detail below, can be implemented in any of a number of ways, because the concepts and embodiments disclosed in the present invention are not limited to any implementation manner. In addition, some aspects of the present invention can be used alone, or in any suitable combination with other aspects disclosed in the present invention.

[0042] In this embodiment, the present invention is described by taking three powder materials (powder material A, powder material B, and powder material C) as examples.

[0043] In the process of LDED space heterogeneous structure materials, when using multiple powder feeding cylinders to alternately pneumatically feed heterogeneous powders (such as nickel-based superalloys, titanium alloys, high entropy alloys, iron-based alloys, etc.) to the same laser head, on the one hand, the previous powder material A remaining in the pneumatic conveying pipeline and the laser head will contaminate the subsequent pneumatically fed powders B, C, etc., thus affecting the purity of the space heterogeneous structure materials; on the other hand, in response to the previous problem, before the laser directed energy deposition of the latter powder B, early powder feeding is started, which can carry out the residual powder A and reduce the powder contamination during deposition, but at the same time, it will also cause a large amount of powder waste. Especially when depositing alloy powders with high deposition costs, the test expenses will be greatly increased. In addition, currently, heterogeneous powder feeding often uses different powder feeding cylinders (powder feeding pipelines) connected to the laser head through joints such as three-way and four-way joints without check valve functions, and the inability to prevent the back blowing of powders will also cause powder contamination. Therefore, the present invention first aims to design a heterogeneous powder feeding and recovery device to achieve the cleaning of the residual powders in the pneumatic conveying pipeline and the laser head and the recovery of heterogeneous powders. At the same time, by increasing the number of air channels of the device, powder feeding of three or more heterogeneous powders can be achieved. In this specification, the example of realizing three heterogeneous powder feedings is taken as an example.

[0044] Further, for the process of LDED space heterogeneous structure materials, taking two powder materials as an example, the current deposition path is mainly to first deposit the 1st, 3rd, and 5th passes of the first layer with powder A, and then deposit the 2nd, 4th, and 6th passes of the first layer with powder B. Then, by rotating 90° between layers, the second layer is deposited with the same deposition path, as Figure 8As shown. Based on the above deposition process, since there is no overlap between the first-deposited single-track clad layers 1, 3, and 5, grooves will appear on the surface of the deposited clad layer (at the original positions of the 2nd and 4th passes). During subsequent deposition, the powder that is not melted by the high-energy laser beam is likely to accumulate in the grooves. Due to the blockage of the single-track clad layers in the same deposition layer, the protective gas / powder-feeding gas ejected by the coaxial laser head cannot completely blow away the powder. When performing LDED for the 2nd, 4th, and 6th passes, on the one hand, the residual powder will cause inclusion defects at the bottom of the 2nd, 4th, and 6th passes in the same deposition layer, and on the other hand, it will also increase the surface roughness of the deposition layer, affecting the accuracy of the deposited part. In addition, based on the current experimental situation, there is also a problem that the clad layers of the 1st, 3rd, and 5th passes deposited first and the clad layers of the 2nd, 4th, and 6th passes deposited later in the same deposition layer are prone to height inconsistencies during the current directed energy deposition process. This usually leads to an uneven surface of the "substrate" during the deposition of the next layer, thereby affecting the deposition accuracy. Layer by layer accumulation will cause the deposition of heterogeneous structure materials to collapse and fail. Regarding the problem of the uneven surface of the above deposition layer, currently, it can be solved by changing process parameters such as the powder-feeding amount and the scanning speed during the deposition of heterogeneous powders. However, the difference in the laser absorption rate of different powders will require re-adjusting the process parameters when changing the type of deposited powder, making the additive process too complicated. There is an urgent need to explore a surface leveling technology for deposition layers that is not affected by the change of deposition materials. Based on this, the present invention also aims to design an additive roller pressing collaborative platform, combined with a ranging sensor, to perform layer-by-layer roller pressing on the upper surface of the deposition layer to level the deposition upper surface and ensure the deposition accuracy. Secondly, the platform is also equipped with a powder cleaning device, and a set of jetting mechanisms distributed in a loop shape is designed. Based on the change of the laser defocus amount, the residual powder at the surface grooves under the layer-by-layer rotation of 90° heterogeneous material deposition path is cleaned through a manual adjustment mechanism to reduce the inclusion risk of heterogeneous structure materials and reduce the surface roughness.

[0045] Furthermore, for LDED space heterogeneous structure materials, due to their special deposition path (i.e., depositing the 1st, 3rd, and 5th passes first and then the 2nd, 4th, and 6th passes), when using the latter material B to deposit the groove part or deposit the next layer, pore defects often occur, that is Figure 8The pore defect 6 in it is caused by the surface tension of the molten metal and the rapid cooling characteristics of LDED, which makes it difficult for gas to completely escape from the groove, resulting in poor bonding strength of the deposited spatially heterogeneous structure material and affecting its comprehensive performance. In addition, the unused powder ejected by the laser head usually cannot be directly recycled due to the change of its structure under the action of thermal radiation, but can be recycled as waste. However, since heterogeneous structure materials require multiple additive powders and the recycling prices of different powder materials vary greatly, it is necessary to classify and collect the additive waste powder. Based on this, the present invention also designs a waste powder screening and collection device, which realizes the classification and collection treatment of additive waste powder in combination with a conveyor belt mechanism (avoiding the powder accumulation in a short time by the positive pressure and negative pressure powder feeding mechanisms and affecting the powder screening effect); in addition, the device is also equipped with an ultrasonic vibration clamping platform, which avoids the problem of a large amount of powder remaining on the previous additive platform through the movable support rod and claw, and further improves the total amount and purity of waste powder collection; finally, the ultrasonic vibration device carried on the platform can greatly reduce the pore defect under the deposition path of heterogeneous materials and further improve the comprehensive performance of heterogeneous structure materials.

[0046] Furthermore, this device can not only better realize the additive manufacturing of spatially heterogeneous structure materials, but also realize conventional additive manufacturing (changing process parameters and powder types), ultrasonic energy field assisted additive manufacturing, and roll pressing additive manufacturing; in addition, this device also adopts a modular design, and according to the additive requirements, the modules can be selectively turned on / off to reduce the overall energy consumption of the device.

[0047] Combined with Figure 1As shown in the figure, in this embodiment, a device for laser additive manufacturing of heterogeneous structure materials is provided, including a device housing 1, a heterogeneous powder feeding and recycling device 2, an additive roll pressing collaborative platform 3, an ultrasonic vibration clamping platform 4, and a powder screening and collection device 5; the heterogeneous powder feeding and recycling device 2 is connected to the powder screening and collection device 5; the additive roll pressing collaborative platform 3 is arranged below the heterogeneous powder feeding and recycling device 2, the ultrasonic vibration clamping platform 4 is arranged below the additive roll pressing collaborative platform 3, and the powder screening and collection device 5 is located below the ultrasonic vibration clamping platform 4; among them, the heterogeneous powder feeding and recycling device 2 can effectively blow out the powder remaining in the powder feeding pipe and the laser head, avoiding subsequent pollution problems; at the same time, the heterogeneous powder remaining in the powder feeding pipe can be recycled into the heterogeneous powder collection box for reuse, improving the powder utilization rate; the powder cleaning mechanism in the additive roll pressing collaborative platform 3 reduces the powder remaining on the surface of the deposition layer, and also helps the subsequent screening and recycling of heterogeneous waste powder. The various component devices of this device can achieve collaborative cooperation between functions; the roll pressing mechanism in the additive roll pressing collaborative platform 3 rolls and presses the upper surface of the deposition layer; when the ultrasonic vibration clamping platform 4 is used for LDED space heterogeneous structure materials, the powder blown out from the surface groove of the deposition layer by the powder cleaning mechanism and other unused powder blown out by the laser head will be blocked by the powder blocking mechanism and fall on the conveyor belt below, which will help the screening and recycling of the powder; the moving clamping platform 4 clamps additive substrates of different sizes; the ultrasonic vibration mechanism contacts the additive substrate, further transmitting the ultrasonic vibration to the additive substrate. By using ultrasonic vibration and cavitation effects, the solidification structure grains of the space heterogeneous structure materials are refined, the composition is uniform, and the pore defects are reduced. The waste powder screening and collection device can achieve the screening and collection of the powder.

[0048] Further, the lowermost end of the device housing 1 is the waste powder screening and collection device housing 11, a cover plate 112 is covered above the waste powder screening and collection device housing 11, a dust-proof housing 12 is fixedly connected to the upper side of the cover plate 112, a cover plate 14 is installed above the dust-proof housing 12, and the cover plate 14 and the dust-proof housing 12 can effectively limit the dispersion range of dust during the additive manufacturing process. Further, the heterogeneous powder feeding and recycling device 2 is arranged at the upper part inside the dust-proof housing 12.

[0049] Furthermore, the heterogeneous powder feeding and recycling device 2 includes a lower base plate 22, a disc seat 23, a rotating circular block 24, a disc 25 and a cover plate 26; the cover plate 26 is fixedly connected to the dust-proof housing 12 by screws. Above the cover plate 26, there are a first powder feeding pipe orifice 261, a second powder feeding pipe orifice 262, a third powder feeding pipe orifice 263 and an air inlet pipe orifice 264. The first powder feeding pipe orifice 261, the second powder feeding pipe orifice 262 and the third powder feeding pipe orifice 263 are all connected to the corresponding A, B, C heterogeneous powder pneumatic conveying pipes, and the air inlet pipe orifice 264 is connected to an inert gas pipe (not shown in the figure). The cover plate 26 is fixedly connected to the disc 25 by screws below. Both the disc 25 and the cover plate 26 are provided with four vertically arranged channels that are closely connected up and down. The channels include an air delivery channel 265, a first powder feeding channel 266, as well as a second powder feeding channel and a third powder feeding channel (not shown in the figure). The air delivery channel 265 is located at the center of the disc 25 and communicates with the air inlet pipe orifice 264 on the upper side. The upper side of the first powder feeding channel 266 communicates with the first powder feeding pipe orifice 261. Specifically, the three components of the first powder feeding channel 266, the second powder feeding channel, the third powder feeding channel and the powder feeding pipe orifice communicating above have the same shape and size, and the horizontal distance between the centers of the channels and the center of the air delivery channel 265 is the same.

[0050] Furthermore, a servo motor 27 is installed above the cover plate 26 near the dust-proof housing 12. The output shaft 271 of the servo motor 27 is fixedly connected to a gear 272 below through holes on the cover plate 26 that correspond in size and position. The gear 272 meshes with an arc rack 273. The arc rack 273 is fixedly connected to the rotating circular block 24. The servo motor 27, the output shaft 271, the gear 272, the arc rack 273, etc. form a rotation driving device for the rotating circular block 24 to drive the rotating circular block 24 to rotate.

[0051] Furthermore, the rotating circular block 24 and the disc 25 are connected by an annular guide rail slider mechanism (not shown in the figure). After receiving a signal, the servo motor 27 drives the rotating circular block 24 to rotate around the central axis of the disc 25 through the output shaft 271, the gear 272 and the arc rack 273.

[0052] Further, a through groove is formed in the rotating circular block 24 in a radial direction, and an opening slider 241 is arranged in the through groove. A duct 2411 is formed in the opening slider 241. At the same time, a linear driving device is fixedly installed on the side of the rotating circular block 24 close to the opening slider 241. The linear driving device includes a servo push rod 242. The output power side of the servo push rod 242 is connected to the inner side of the outer end face of the opening slider 241. When the servo push rod 242 receives a signal, it can drive the opening slider 241 to move back and forth radially in the rotating circular block 24. Further, the lower side of the rotating circular block 24 is connected to the disc seat 23 through an annular guide rail slider mechanism (not shown in the figure). The disc seat 23 is fixedly connected to the lower bottom plate 22 by screws. The lower bottom plate 22 is fixedly installed on the dust-proof housing 12. Corresponding holes are formed in the disc seat 23 and the lower bottom plate 22 at the same vertical positions of the four ducts of the disc 25. The holes include a central duct 231, a first powder recovery pipeline 232, and second and third powder recovery pipelines (not shown in the figure). A powder feeding pipe 21 is connected below the central duct 231. The other end of the powder feeding pipe 21 is connected to the laser head 318. The first powder recovery pipeline 232 is connected to the heterogeneous powder collection box 51 through a pipeline (not shown in the figure).That is, when performing additive manufacturing of spatially heterogeneous structure materials, first, the inert gas pipeline communicates with the air inlet 264, and the gas cylinder connected to the inert gas pipeline is always open. The powder pipeline connected to the first powder feeding port 261 starts to pneumatically transport powder A to the heterogeneous powder feeding and recycling device 2 through the powder feeding equipment. At this time, the servo motor 27 is not turned on, the rotating block 24 is in the initial position (0°), the servo push rod 242 is not opened (the rod is in the shortest extended state), and the inner end face of the opening slider 241 is in seamless contact with the rotating block 24, blocking the communication between the air vent channel 265 and the central channel 231. At this time, the inert gas cannot be further transported through the air vent channel 265. The upper side of the channel 2411 on the opening slider 241 communicates with the first powder feeding channel 266, and the lower side communicates with the central channel 231. Powder A is transported to the laser head 318 through the first powder feeding port 261, the first powder feeding channel 266, the channel 2411, the central channel 231, and the powder feeding tube 21, and is deposited after coaxial powder feeding and melting to form a cladding layer of material A. When a layer of material A is deposited, the servo push rod 242 receives an electrical signal and is turned on, pushing the opening slider 241 to move smoothly along the through groove towards the outside of the rotating block 24. At this time, the inner end face of the opening slider 241 gradually separates from the rotating block 24, forming a cavity, thus connecting the air vent channel 265 and the central channel 231. The inert gas enters the powder feeding tube 21 and the laser head 318 through the above channels. Since the cavity formed by the inner side of the opening slider 241 and the rotating block 24 is small at the beginning stage, the flow rate of the inert gas at this time is fast, which can effectively blow out the residual powder A in the powder feeding tube 21 and the laser head 318, avoiding subsequent pollution problems. At the same time, as the opening slider 241 moves further, the position of the channel 2411 on it is translated, and the lower side of the channel 2411 no longer communicates with the central channel 231, but gradually communicates with the first powder recovery channel 232. Powder A is recovered into the heterogeneous powder collection box 51 through the first powder feeding port 261, the first powder feeding channel 266, the channel 2411, the first powder recovery channel 232, and the subsequent connected pipelines (not shown in the figure) for reuse, improving the powder utilization rate. Then the powder feeding device is turned off, and the collection of powder A is completed. After the set residual powder cleaning time has passed, the servo push rod 242 pulls the opening slider 241 to move along the through groove towards the inside of the rotating block 24 and is in seamless contact with it, and the cavity disappears, and the central channel 231 no longer transports inert gas.Then, start depositing another material B. The servo motor 27 receives an electrical signal and generates power to drive the rotating block 24 to rotate ±90° relative to the disk 25 and the disk seat 23 through the output shaft 271, the gear 272, and the arc rack 273. At this time, the upper side of the duct 2411 on the opening slider 241 is no longer communicated with the first powder feeding duct 266, but is communicated with the second / third powder feeding duct. Then, the powder pipeline connected to the second powder feeding pipe orifice 262 starts to pneumatically convey the powder B to the heterogeneous powder feeding and recovery device 2 through the powder feeding equipment control, and repeat the above operations to achieve the deposition and recovery of the material B.

[0053] Finally, it should be further noted that this embodiment only illustrates the heterogeneous powder feeding and recovery device 2 with three heterogeneous materials as an example, and it can also be designed into four, five powder materials, etc. according to actual needs. By replacing the lower base plate 22, the disk seat 23, the disk 25, and the cover plate 26, the number of powder feeding pipe orifices and ducts of the heterogeneous powder feeding and recovery device 2 can be increased or decreased to make the device more flexible.

[0054] Furthermore, an additive roller pressing collaborative platform 3 is installed in the middle section of the inner wall of the dust-proof housing 12. Specifically, the additive roller pressing collaborative platform 3 is composed of a 3D additive mechanism, a powder cleaning mechanism 32, and a roller pressing mechanism 33. The powder cleaning mechanism 32 and the roller pressing mechanism 33 are installed at the bottom of the 3D additive mechanism.

[0055] The described 3D additive mechanism includes a first rectangular frame 31. Four sliders 311 are symmetrically and fixedly connected to the outside of the long sides of the first rectangular frame 31 (the long sides are parallel to the Y direction). The sliders 311 cooperate with the limit guide rails 312 to form four groups of slider guide rail mechanisms. The limit guide rails 312 are fixedly connected to the inner wall of the middle section of the dust-proof housing 12 by screws. In addition, a slider self-locking screw 313 is also installed on the slider 311. After receiving a signal, the slider self-locking screw 313 locks the slider 311 on the limit guide rail 312 so that it can no longer slide relative to each other. The first rectangular frame 31 is driven by a Z-direction driving mechanism 314 to achieve smooth up and down (Z-direction) movement through four groups of guide rail slider mechanisms. Specifically, the Z-direction driving mechanism 314 consists of a servo motor 3141, a coupling 3142, a lead screw 3143, a guide rod 3144, and a T-shaped nut seat 3145. The two servo motors 3141 are symmetrically and fixedly installed above the long sides of the first rectangular frame 31. The servo motor 3141 is connected to the lead screw 3143 through the coupling 3142. The lead screw 3143 cooperates with the nut in the T-shaped nut seat 3145. The T-shaped nut seat 3145 is fixedly connected to the inner side wall of the dust-proof housing 12 by screws. In addition, four vertical guide rods 3144 extend fixedly from the housing of the servo motor 3141. The guide rods 3144 pass upward through the holes corresponding in size and position on the T-shaped nut seat 3145. By moving up and down of the four guide rods 3144 in the holes, it is ensured that the force can be vertically transmitted when the lead screw 3143 rotates. When performing LDED space heterogeneous structure materials, after one layer of deposition is completed, a signal is sent from the 3D additive mechanism signal processor (not shown in the figure) to the servo motor 3141. After receiving the signal, the servo motor 3141 drives the coupling 3142 and the lead screw 3143 to rotate. Since the T-shaped nut seat 3145 is fixedly installed on the inner side wall of the dust-proof housing 12, the rotation of the lead screw 3143 in the nut can drive the servo motor 3141 and the first rectangular frame 31 connected thereto to rise by the set Z-axis lift amount in the signal for the next layer of deposition work.In addition, symmetric grooves are formed on the inner side of the long side of the first square frame 31 (the long side is parallel to the Y direction), and a second square frame 316 is installed in the grooves. The second square frame 316 can be driven by a Y-direction servo motor (not shown in the figure) to move along the long side (Y direction). In addition, a bladder 315 is also installed in the grooves. The bladder 315 can play a role in buffering and absorbing shocks when the second square frame 316 moves, and isolate the external environment to reduce its impact on the internal precision drive parts. Further, a mounting frame 317 is built on the second square frame 316. The mounting frame 317 is matched with the second square frame 316 through rollers, and a laser head 318 is fixedly mounted on the mounting frame 317. The mounting frame 317 can be driven by an X-direction servo motor (not shown in the figure) to drive the laser head 318 to move along the X direction. That is, three sets of independently operating drive mechanisms can realize the single-axis and multi-axis coordinated movement of the laser head 318 in the X, Y, and Z directions to meet the requirements of conventional additive paths.

[0056] Further, the powder cleaning mechanism includes an air inlet port 321, a labor-saving handle 322, a rotating rod 323, a bevel gear set 324, a bearing seat 325, a jet assembly 326, an air delivery pipe 3261, a sealed housing 3262, an annular airbag 3263, and a nozzle 3264. Four rotating rods 323 are installed below the first square frame 31 through a plurality of bearing seats 325. The bearing seats 325 are fixedly connected to the lower side of the first square frame 31 by screws. The four rotating rods 323 pass through the bearing seats 325 and are connected by four groups of bevel gear sets 324. The bevel gear sets 324 can make the four rotating rods 323 rotate synchronously by the same angle (the angle with the vertical direction). In addition, a jet assembly 326 is installed on the rotating rod 323.

[0057] Specifically, the jet assembly 326 is composed of an air delivery pipe 3261, a sealed housing 3262, an annular airbag 3263, and a nozzle 3264. The air delivery pipe 3261 is located below the first square frame 31. There is an air passage (not shown in the figure) in the first square frame 31 that communicates with it. An air inlet port 321 is installed above the air passage of the first square frame 31. The air inlet port 321 is connected to an inert gas pipeline. The lower part of the air delivery pipe 3261 is fixedly connected to a sealed housing 3262. The sealed housing 3262 and the annular airbag 3263 can rotate relative to each other. A closed cavity can be formed between the annular airbag 3263 and the sealed housing 3262. Inert gas can enter the closed cavity through the air inlet port 321 and the air delivery pipe 3261. The annular airbag 3263 is fixedly connected to the transmission rod 323. When the transmission rod 323 rotates, it can drive the annular airbag 3263 to rotate together. In addition, a conical nozzle 3264 is provided on the annular airbag 3263. The inert gas entering the closed cavity is ejected from the nozzle 3264 under the action of pressure, and can clean the residual powder at the grooves of the deposited heterogeneous structure material.

[0058] In addition, an L-shaped cabinet door 13 is provided at the right front of the dust-proof housing 12. The L-shaped cabinet door 13 is installed on the dust-proof housing 12 through a door shaft 132. A handle 131 is installed on the outer side of the L-shaped cabinet door. Before performing the LDED spatial heterostructure material, the L-shaped cabinet door 13 can be opened for related operations. Further, a rotating rod 323 adjacent to and perpendicular to the L-shaped cabinet door 13 extends toward the L-shaped cabinet door 13 side. A labor-saving handle 322 is installed on the extended section of the rotating rod 323. The labor-saving handle 322 is marked with a pointer and the first return-shaped frame 31 is marked with corresponding defocus amount scales. That is, before performing the LDED spatial heterostructure material, first open the L-shaped cabinet door 13. According to the defocus amount value f set for this LDED test, manually rotate the labor-saving handle 322 so that the pointer on it points to the corresponding defocus amount value f to complete the setting. When the labor-saving handle 322 is rotated, the rotating rod 323 connected to it and other rotating rods 323 connected through a bevel gear set 324 will rotate by the same angle. At the same time, the annular airbag 3263 fixedly connected to the rotating rod 323 and the nozzle 3264 thereon also rotate by the corresponding angle, ensuring that the inert gas ejected from the nozzle 3264 can clean the powder remaining in the groove formed on the lower surface of the deposition path of the spatial heterostructure material. Subsequently, close the cabinet door 13 to control the dispersion range of the dust, which is helpful for the next powder recovery work.

[0059] Furthermore, an example of cleaning the residual powder under the deposition path of the spatial heterogeneous structure by the powder cleaning mechanism is introduced. That is, when the deposition path direction is perpendicular to the long side of the first square frame 31 (perpendicular to the Y direction), after depositing the 1st, 3rd, and 5th cladding layers of a certain A material, the powder cleaning mechanisms 32 on both sides below the long side of the first square frame 31 start to cross-jet high-pressure inert gas. Since the direction of the high-pressure inert gas is consistent with the direction of the grooves on the surface of the deposition layer (the positions of the 2nd and 4th layers of the B material to be deposited), the deposited 1st, 3rd, and 5th cladding layers will not block the inert gas and can fully clean the residual A powder in the grooves. When a layer is deposited and the deposition path rotates 90°, at this time, the deposition path direction is parallel to the long side of the first square frame 31 (parallel to the Y direction). After depositing the 1st, 3rd, and 5th cladding layers of the A material, the powder cleaning mechanisms 32 on both sides below the short side of the first square frame 31 start to cross-jet high-pressure inert gas (the gas is parallel to the Y direction), effectively removing the powder remaining on the deposition surface, reducing the inclusion defects between different deposition layers, and improving the surface quality of the additive. At the same time, since the inert gas ejected plays a role of forced convection on the surface of the spatial heterogeneous structure material, it helps to reduce the heat accumulation during deposition and improve the material properties. By adjusting the flow rate of the inert gas introduced, the strength of the forced convection can be controlled to adjust the cooling rate of the deposition specimen surface. In addition, the powder cleaning mechanism 32 reducing the powder remaining on the surface of the deposition layer also helps with the subsequent screening and recycling of heterogeneous waste powder. The various component devices of this device can achieve coordinated cooperation between functions.

[0060] Further, the roll pressing mechanism 33 includes a servo cylinder 331, a mandrel 332, a roll 333, and a chute 334. Chutes 334 are symmetrically formed on the lower side of the long side of the first loop-shaped frame 31. Sliders are fitted in the chutes 334. A servo cylinder 331 is fixedly connected below the sliders. The lowermost end of the servo cylinder 331 is connected to a bearing block for mounting the mandrel 332. The roll 333 is disposed outside the mandrel 332. That is, when performing LDED spatial heterogeneous structure materials, after one layer of deposition is completed, the slider receives a signal from the self-locking screw 313 and locks the slider 311 on the limit guide 312. At this time, the first loop-shaped frame 31 is fixed, and a distance measuring sensor (not shown in the figure) is installed below the first loop-shaped frame 31. The distance measuring sensor measures the distances between multiple discrete points selected from the upper surface of the deposition layer and the defined origin and sends the test signals to a signal processor (not shown in the figure). The signal processor analyzes multiple groups of measurement data, determines the concavity and convexity of the upper surface of the deposition layer, and gives a reasonable roll pressing downward amount. Subsequently, after the servo cylinder 331 receives the above signal, it adjusts the telescopic amount to reach the set downward amount, and drives the roll 333 to move smoothly along the chute 334 under the action of a Y-direction servo motor (not shown in the figure). The roll 333 rolls around the mandrel 332 and presses the upper surface of the deposition layer. Since the first loop-shaped frame 31 is fixed, sufficient support force can be provided to the roll pressing mechanism 33. At the same time, the distance measuring sensor continuously feeds back the flatness of the upper surface of the deposition layer. When the flatness reaches the expected requirement, the roll pressing is stopped, and the self-locking screw 313 of the slider is unlocked. At this time, the signal processor analyzes and calculates the distance between the upper surface of the final deposition layer and the 3D printing mechanism 31, and recalibrates the actual Z-axis lifting amount z2 in combination with the pre-set Z-axis lifting amount z1 to ensure that the defocus amount during LDED remains unchanged. The signal is transmitted to the servo motor 3141. After receiving the signal, the servo motor 3141 lifts the first loop-shaped frame 31 by z2 by rotating the lead screw 3143, and then the next layer of deposition is performed.

[0061] Furthermore, an ultrasonic vibration clamping platform 4 is installed on the inner wall of the lower section of the dustproof shell 12. Specifically, the ultrasonic vibration clamping platform 4 is composed of a slider hinge mechanism 41, a support rod 42, a powder blocking mechanism 43, a movable clamping platform 44, a telescopic mechanism 45, a servo double-rod hydraulic cylinder 46 and an ultrasonic vibration platform 47. The two ends of the support rod 42 are placed in a rectangular hole that passes through the dustproof shell 12 on the same horizontal plane. A slide plate 413 is installed in the rectangular hole and is sleeved on the support rod 42. The slide plate 413 is embedded in a slide rail (parallel to the shell surface, not shown in the figure) provided in the middle layer of the anti-slip shell 12. Since the size of the slide plate 413 is larger than the size of the rectangular hole, when the slide plate 413 moves synchronously with the support rod 42 in the horizontal X direction, the slide plate 413 can close the rectangular hole to prevent the escape of powder during LDED spatial heterogeneous structure material. The support rod 42 is fixedly connected to a horizontal slider 412 at one end outside the dustproof housing 12. The horizontal slider 412 is placed in a limiting slide groove 411 and is hinged to a connecting rod 415. The other end of the connecting rod 415 is connected to a vertical slider 418 through a hinge 417. The vertical slider 418 is sleeved on a guide slide rod 416. The guide slide rod 416 is fixed on a slide rod seat 414 and a slide rod bracket 419. The slide rod seat 414 and the slide rod bracket 419 are fixed to the dustproof housing by screws. 12, that is, when the support rod 42 moves in the X direction, it will drive the horizontal slider 412 to slide horizontally along the limiting slide groove 411, and then drive the vertical slider 418 to slide vertically along the guide slider 416 through the connecting rod 415. However, since the horizontal sliders 412 fixedly connected to the two support rods 42 are hinged to the same vertical slider 418 through the connecting rod 415, the horizontal slider 412 and the support rod 42 are restricted to only slide synchronously and symmetrically, ensuring that the center of the connection line of the two support rods 42 is always on the YZ plane. Furthermore, a powder blocking mechanism 43 is provided on the support rod 42 inside the dustproof housing 12. Specifically, the powder blocking mechanism 43 is composed of a powder blocking plate 431, a spring spring 432 and a Teflon film 433 (high temperature resistant). The baffle plate 431 is sleeved on the support rod 42 and can slide relatively manually. The Teflon film 433 is connected to the spring spring 432. When the support rod 42 slides in a direction away from the YZ plane, the Teflon film 433 is pulled out from the spring spring 432. When the support rod 42 slides in a direction close to the YZ plane, the Teflon film 433 is affected by the restoring force of the spring spring 432. And rewind it to ensure that the width of the powder blocking mechanism 43 always matches the distance between the two support rods 42. At the same time, according to the size of the placed additive substrate, the position of the powder blocking mechanism 43 on the support rod 42 can be manually adjusted (moved along the Y direction). When LDED spatial heterogeneous structure materials, the powder blown out from the grooves on the surface of the deposition layer by the powder cleaning mechanism 32 and other unused powder blown out by the laser head 318 will be blocked by the powder blocking mechanism 43 and fall on the conveyor belt 522 below. The arc surface design on the upper part of the support rod 42 is not conducive to the residue of powder. The above design will help to recover the powder. Further,A movable clamping platform 44 is fixedly installed on the middle section of the support rod 42. One first clamping assembly 441 and two second clamping assemblies 442 are installed on the movable clamping platform 44 respectively. Specifically, the first clamping assembly 441 is composed of a first claw 4411 and a first adjustment knob 4412. By rotating the first adjustment knob 4412, the up-and-down position adjustment of the first claw 4411 can be realized through a built-in lead screw nut mechanism (the lead screw rotates and the nut moves, not shown in the figure) to cope with additively manufactured substrates of different thicknesses. In addition, a telescopic mechanism 45 is arranged between the inner end faces of the movable clamping platform 44. Specifically, the telescopic mechanism 45 is composed of a folding frame 451, a slider 452, a chute 4521, and a rotating shaft 453. At the same time, a servo double-rod hydraulic cylinder 46 is installed between the movable clamping platforms 44. One end of each side of the folding frame 451 is fixedly connected to the slider 452 and the rotating shaft 453 respectively. The two rods of the servo double-rod hydraulic cylinder 46 are fixed on the inner end faces of the movable clamping platform 44. That is, during the stage of clamping the additively manufactured substrate before LDED, the servo double-rod hydraulic cylinder 46 receives a signal and starts to control the telescopic rods on both sides to drive the movable clamping platform 44 to move a certain distance away from the YZ plane (there is enough space in the space to place the substrate). Since the movable clamping platform 44 is fixed on the support rod 42, due to the limitation of the slider hinge mechanism 41, the support rod 42 and the movable clamping platform 44 can only move synchronously and symmetrically along the YZ plane. As a result, the position of the cylinder body of the servo double-rod hydraulic cylinder 46 remains unchanged. As the movable clamping platform 44 moves to both sides, the folding frame 451 extends, and the slider 452 fixedly connected to one end of the folding frame starts to slide along the chute 4521, and the rotating shaft 453 connected to the other end rotates by a corresponding angle, ensuring the stability of the overall mechanism and preventing the movable clamping platform 44 from tilting during movement. Then, open the L-shaped cabinet door 13 on the dust-proof housing 12, place the additively manufactured substrate on the movable clamping platform 44. The servo double-rod hydraulic cylinder 46 controls the telescopic rods on both sides to drive the movable clamping platform 44 to return until the first claw 4411 touches the side of the additively manufactured substrate and then slowly contracts. A pressure sensor (not shown in the figure) is mounted on the first claw 4411. When the measured value of the pressure sensor reaches a predetermined value, it transmits an instruction to control the servo double-rod hydraulic cylinder 46 to stop working. At this time, the entire movable clamping platform 44 has been hidden under the additively manufactured substrate, and only a pair of first claws 4411 are clamped on both sides of the substrate. At the same time, the second clamping mechanism 442 also fixes the substrate from other sides; specifically, the second clamping assembly 442 is composed of a second claw 4421, a second claw slide plate 4423, and a second adjustment knob 4424. The second claw 4421 is sleeved on the second claw slide plate 4423 (to prevent powder from remaining on the claw slide plate), and the upper part of the second claw 4421 (the first claw 4411) is designed to be inclined. Combined with the blowing action of the inert gas ejected by the gas jet assembly 326 on the additive rolling collaborative platform 3, it can effectively reduce the powder remaining on the claws when manufacturing space heterogeneous structure materials by LDED. On the one hand, it can improve the recovery rate of waste powder,On the other hand, it can ensure that after the deposition of material A powder, there is as little residual material A powder as possible on the entire ultrasonic vibration platform, avoiding contamination of the material B powder to be recycled in the next step. Similarly, by rotating the second adjustment knob 4424, the second jaw 4421 can also be adjusted to move up and down along the second jaw slide plate 4423. In addition, an anti-slip groove 4422 is designed on the second jaw 4421 to enhance the clamping force and stability. A telescopic rod 454 is fixedly connected to the inner wall of the second jaw slide plate 4423. The telescopic rod 454 is installed in a hole machined on the side of the moving clamping platform 44. A spring 455 is sleeved on the telescopic rod 454. The spring 455 is located between the side of the moving clamping platform 44 and the inner wall of the second jaw slide plate 4423. That is, according to the Y-direction dimension of the additive substrate size, the second jaw slide plate 4423 is pulled to the side of the additive substrate, and the second jaw 4421 is clamped to the side of the additive substrate by the restoring force of the spring 455. The final clamping state is that only three pairs of jaws are clamped to the side of the substrate to ensure as little residual powder as possible on the platform.

[0062] Furthermore, an ultrasonic vibration mechanism 47 is also installed in the middle of the moving clamping platform 44. Specifically, the ultrasonic vibration mechanism 47 is composed of a ultrasonic transducer 471, a support plate 472, a support table 473, a damping pedestal 474 and an ultrasonic vibration platform 475. The ultrasonic transducer 471 is installed on the vertical support plate 472 and is connected to a ultrasonic generator (not shown in the figure). The support plate 472 is fixed to the support table 473 by screws. The support table 473 is fixed to the lower part of the cylinder body of the servo double-rod hydraulic cylinder 46 by a riding buckle 461. A damping platform 474 is also installed on the support table 473. The ultrasonic vibration platform 475 is installed above the damping platform 474. The side of the octagonal prism fixedly connected to the lower part of the ultrasonic vibration platform 475 is in contact with the output end of the ultrasonic transducer 471. That is, when performing LDED space heterostructure materials, synchronously, the ultrasonic transducer starts to work, and the generated ultrasonic vibration directly acts on the ultrasonic vibration platform 475. The upper part of the ultrasonic vibration platform 475 is in contact with the additive substrate, and further transmits the ultrasonic vibration to the additive substrate. By using ultrasonic vibration and cavitation effects, the solidification structure grains of the space heterostructure materials are refined, the composition is made uniform, and the pore defects are reduced.

[0063] Furthermore, in terms of spatial position, a powder screening and collecting device 5 is designed below the ultrasonic vibration clamping platform 4. Specifically, the powder screening and collecting device 5 consists of a heterogeneous powder collection box 51 and a waste powder conveying and screening mechanism 52. Specifically, the waste powder conveying and screening mechanism 52 consists of a partition 521, a conveyor belt 522, a moving funnel 523, a funnel driving assembly 524, a powder screening mechanism 525, a powder screening driving assembly 526, and a support frame 527. The partition 521 is installed between the cover plate 112 and the conveyor belt support frame 527. The inner wall of the partition 521 parallel to the moving direction of the conveyor belt is smoothed to facilitate the sliding of waste powder onto the conveyor belt 522. In addition, a closing baffle 5211 is integrally connected to the partition 521 at the end of the conveyor belt 522. A scraper (not shown in the figure) is provided between the end of the conveyor belt 522 and the moving funnel 523. The moving funnel 523 can be driven by the funnel driving assembly 524 to move along a chute 5233 processed on the support plate 5232.

[0064] Specifically, the funnel driving assembly 524 consists of a motor base 5241, a servo motor 5242, a gear 5243, and a straight rack 5244. The straight rack 5244 is provided above the moving funnel 523 and meshes with the gear 5243. The gear 5243 is fixed to the output shaft of the servo motor 5242. The servo motor 5242 is installed in the motor base 5241. The motor base 5241 is fixedly connected to the lower side of the cover plate 112 by screws. A powder outlet 5231 is processed at the bottom of the moving funnel 523. The additive waste powder is conveyed to the powder screening mechanism 525 through the powder outlet 5231.

[0065] Specifically, the powder screening mechanism 525 consists of a powder baffle 5251, a coarse particle powder collection box 5253, a fine particle powder collection box 5255, universal rolling balls 5256, and an inclined panel 5257. The inclined panel 5257 is divided into three parts by the powder baffle 5251, corresponding to the screening areas of waste powder of material A, waste powder of material B, and waste powder of material C. In addition, fine sieve holes 5254 are processed on the upper half surface of the inclined panel 5257. The fine particle powder collection box 5255 is installed below the inclined panel 5257 with the fine sieve holes 5254. Coarse sieve holes 5252 are processed on the lower half surface of the inclined panel 5257. The coarse particle powder collection box 5253 is installed below the inclined panel 5257 with the coarse sieve holes 5252. The powder collection box is movably connected with universal rolling balls 5256 below to support the powder collection box. The universal rolling balls 5256 are embedded in hemispherical holes of appropriate sizes processed on the bottom plate of the waste powder collection device housing 11. Further, the powder screening mechanism 525 realizes the powder screening function through the reciprocating drive of the powder screening driving assembly 526.

[0066] Specifically, the powder screening drive assembly 526 is composed of a motor base 5261, a servo motor 5262, an eccentric wheel 5263, a disc 5264, a transmission rod 5265, a spring 5266, a support plate 5267, and a support spring 5268. The motor base 5261 is fixedly connected to the upper side of the bottom plate of the waste powder collection device housing 11. The servo motor 5262 is installed in the motor base 5261, and the output shaft of the servo motor 5262 is fixedly connected to the eccentric wheel 5263. The side of the eccentric wheel 5263 is in contact with the disc 5264. The center of the disc 5264 is connected to a transmission rod 5265. The transmission rod 5265 horizontally passes through a corresponding through hole machined in the support plate 5267. A spring 5266 is sleeved on the transmission rod 5265 between the disc 5265 and the support plate 5267. A reciprocating block 5269 is fixedly installed at the end face of the transmission rod 5265. The other side of the reciprocating block 5269 is slidably connected to the side of the powder collection box. A support spring 5268 is installed between the support plate 5267 and the side of the powder collection box.

[0067] In addition, a fixed card slot 1112 is fixedly connected to the inner wall of the first pull-out door 111. The fixed card slot 1112 is used to fix the support plate 5267 to prevent the support plate 5267 from shaking under the reciprocating movement of the transmission rod 5265. The support spring 5268 and the universal balls 5256 cooperate to achieve the reciprocating vibration and support of the powder screening mechanism 525.

[0068] When fabricating LDED spatial heterogeneous structure materials, after depositing the A powder in one layer, the powder cleaning mechanism 32 blows off the A powder remaining in the grooves on the surface of the deposited layer and on the ultrasonic vibration clamping platform 4. The blown A powder falls onto the conveyor belt 522 under the action of the powder blocking mechanism 43 and the dust-proof housing 12. After that, the conveyor belt starts to transport the waste A powder. When the A powder is transported to the end of the conveyor belt 522, the closing baffle 5211 gathers the waste A powder, and the gathered waste A powder is guided to the movable funnel 523 by a scraper (not shown in the figure). At this time, the powder outlet 5231 corresponds to the area on the inclined panel 5257 of the powder screening mechanism 525 corresponding to the A powder. Meanwhile, the servo motor 5262 receives a signal and starts to drive the eccentric wheel 5263 to rotate. Under the coordinated action of the eccentric wheel 5263 and the return spring 5266, the disc 5264 and the transmission rod 5265 start to reciprocate horizontally, and the power is transmitted to the powder collection box through the reciprocating block 5269 to realize the vibration of the powder screening mechanism. Then, the waste A powder on the inclined panel 5257 first passes through the fine sieve hole area, and the powder that is not melted but only affected by heat radiation passes through the fine sieve holes 5254 and falls into the fine particle powder collection box 5255, while the waste materials such as melted or splashed materials generated during LDED fall into the coarse particle powder collection box 5253 through the coarse sieve holes 5252 below the inclined panel 5257. After the conveyor belt 522 rotates half a circle, it will stop moving, and then the B powder will be deposited. At the same time, the servo motor 5242 starts to work and drives the movable funnel 523 to slide along the chute 5233 to move the powder outlet 5231 to the B powder screening area for subsequent screening work.

[0069] Further, the housing 11 of the waste powder collection device is composed of a first pull-out door 111, a first pull handle 1111, a cover plate 112, a second pull-out door 113, and a second pull handle 1131. That is, after the deposition work is completed, pulling open the first pull-out door 111 can take out the collected heterogeneous waste powder, and pulling open the second pull-out door 113 can take out the collected reusable heterogeneous powder.

[0070] The present invention systematically solves the problems of powder pollution, surface flatness, pore defects, and waste powder recycling in the additive manufacturing of heterogeneous structure materials. This device can not only achieve high-quality additive manufacturing of spatial heterogeneous structure materials but also adapt to conventional additive manufacturing and various additive processes (such as ultrasonic-assisted, roll pressing additive, etc.).

Claims

1. A system for additive manufacturing of spatial heterogeneous structure materials, characterized in that: It includes a heterogeneous powder feeding and recovery device, an additive roller pressing collaborative platform, an ultrasonic vibration clamping platform and a powder screening and collecting device; the heterogeneous powder feeding and recovery device includes a lower bottom plate, a disc seat, a rotating round block, a disc and a cover plate; a plurality of powder feeding pipe openings and air inlet pipe openings are arranged above the cover plate, the lower part of the cover plate is fixedly connected to the disc, and the disc and the cover plate are both provided with air delivery channels and powder feeding channels that are closely connected up and down, the air delivery channel is located at the center of the disc, the upper side is connected to the air inlet pipe opening, and the upper side of the powder feeding channel is connected to the powder feeding pipe opening, the lower part of the disc is a rotating round block, the rotating round block is connected to the rotating driving device, a through groove is opened on the rotating round block along a radial direction, an open hole slider is arranged in the through groove, A hole is opened on the perforated slider, and the perforated slider is connected to the linear drive device. The lower side of the rotating round block is connected to the disc seat through an annular guide rail slider mechanism. The disc seat is fixedly connected to the lower base plate. The disc seat and the lower base plate have corresponding central holes and powder recovery pipes at the same vertical position of the four holes of the disc. A powder feeding pipe is connected below the central hole, and the other end of the powder feeding pipe is connected to the laser head. The remaining powder recovery pipes are connected to the collection box in the powder screening and collection device through pipes; the additive roller pressing collaborative platform is arranged below the heterogeneous powder feeding and recovery device, the ultrasonic vibration clamping platform is arranged below the additive roller pressing collaborative platform, and the powder screening and collection device is located below the ultrasonic vibration clamping platform.

2. The system for additive manufacturing of spatial heterogeneous structure materials according to claim 1, characterized in that: The additive rolling platform is composed of a 3D additive mechanism, a powder cleaning mechanism and a rolling mechanism. The 3D additive mechanism includes a first round frame, which is connected to the inner wall of the middle section of the dustproof shell through a slider guide mechanism on the outside of the first round frame, and the first round frame is moved up and down by a Z-direction driving mechanism; a second round frame is installed on the inner side of the first round frame, and the second round frame is driven by a Y-direction driving mechanism to move in the first round frame along the Y direction, and a mounting frame is mounted on the second round frame, and the mounting frame is provided with a laser head, and the laser head mounting frame moves along the X direction under the drive of the X-direction driving mechanism; a powder cleaning mechanism and a rolling mechanism are installed at the bottom of the first round frame.

3. The system for additive manufacturing of spatial heterogeneous structure materials according to claim 2, characterized in that: The powder cleaning mechanism includes a rotating rod and a jet assembly. Four rotating rods are installed under the first circular frame through multiple bearing seats. The bearing seats are fixedly connected to the lower side of the first circular frame. The four rotating rods pass through the bearing seats and are connected by four sets of bevel gear sets. The bevel gear sets can realize the synchronous rotation of the four rotating rods at the same angle. The jet assembly is installed on the rotating rod.

4. The system for additive manufacturing of spatial heterogeneous structure materials according to claim 3, characterized in that: The jet assembly consists of an air pipe, a sealed shell, an annular airbag and a nozzle. The air pipe is located below the first round frame. The first round frame has an air passage communicating therewith. An air inlet port is installed above the air passage of the first round frame. The air inlet port is connected to the inert gas pipeline. A sealed shell is fixedly connected below the air pipe. The sealed shell and the annular airbag can rotate with each other. A closed cavity can be formed between the annular airbag and the sealed shell. The annular airbag is fixedly connected to a transmission rod. A conical nozzle is provided on the annular airbag.

5. The system for additive manufacturing of spatial heterogeneous structure materials according to claim 3, characterized in that: The rolling mechanism includes a servo cylinder, a core shaft and a roller; a slide groove is symmetrically opened on the lower side of the long side of the first circular frame, a slider is matched in the slide groove, a servo cylinder is fixedly connected below the slider, a bearing seat is connected to the lower end of the servo cylinder, the bearing seat is used to install the core shaft, and the outer side of the core shaft is a roller; and a distance measuring sensor is arranged below the first circular frame, and a self-locking device is installed on the slider connecting the guide rail of the first circular frame.

6. The system for additive manufacturing of spatial heterogeneous structure materials according to claim 3, characterized in that: The ultrasonic vibration clamping platform is composed of a slider hinge mechanism, a support rod, a powder blocking mechanism, a mobile clamping platform and an ultrasonic vibration platform. The two ends of the support rod are placed in rectangular holes that pass through the dustproof shell on the same horizontal plane. A slide plate is installed in the rectangular hole and is sleeved on the support rod. The slide plate is embedded in a slide groove provided in the middle layer of the dustproof shell. The size of the slide plate is larger than the size of the rectangular hole. A slider hinge mechanism is fixedly connected to one end of the support rod on the outside of the dustproof shell; a powder blocking mechanism is also provided on the support rod inside the dustproof shell; a mobile clamping platform is fixedly installed on the middle section of the support rod; and an ultrasonic vibration mechanism is also carried in the middle of the mobile clamping platform.

7. The system for additive manufacturing of spatial heterogeneous structure materials according to claim 3, characterized in that: The slider hinge mechanism includes a horizontal slider, which is placed in a limiting slide groove and hinged with a connecting rod. The other end of the connecting rod is connected to a vertical slider through a hinge. The vertical slider is sleeved on a guide slide rod, and the guide slide rod is fixed on a slide rod seat and a slide rod bracket. The slide rod seat and the slide rod bracket are fixedly connected to the outer wall of the dustproof shell.

8. The system for additive manufacturing of spatial heterogeneous structure materials according to claim 3, characterized in that: The powder blocking mechanism is composed of a powder blocking plate, a spring and a Teflon film. The blocking plate is sleeved on the support rod and can slide relatively manually. The Teflon film is connected to the spring.

9. The device for additive manufacturing of spatial heterogeneous structure materials according to claim 1, characterized in that: The powder screening and collecting device is composed of a heterogeneous powder collection box and a waste powder conveying and screening mechanism. The waste powder conveying and screening mechanism is composed of a partition, a conveyor belt, a mobile funnel, a funnel driving assembly, a powder screening mechanism, a powder screening driving assembly and a support frame. The partition is installed between the cover plate and the conveyor belt support frame. The partition is integrally connected with a closing baffle above the rear end of the conveyor belt. A scraper is provided between the rear end of the conveyor belt and the mobile funnel. The mobile funnel can be driven by the funnel driving assembly to move along the slide groove processed on the support plate; a powder outlet is processed at the bottom of the mobile funnel, and the additive waste powder is transported to the powder screening mechanism through the powder outlet.

10. The system for additive manufacturing of spatial heterogeneous structure materials according to claim 9, characterized in that: The powder screening mechanism is composed of a powder baffle plate, a coarse-grained powder collection box, a fine-grained powder collection box, a universal rolling ball and an inclined panel. The inclined panel is divided into three parts by the powder baffle plate, which correspond to waste powder screening areas of different materials respectively. Fine sieve holes are processed on the surface of the upper half of the inclined panel, and a fine-grained powder collection box is installed below the inclined panel with fine sieve holes. Coarse sieve holes are processed on the surface of the lower half of the inclined panel, and a coarse-grained powder collection box is installed below the inclined panel with coarse sieve holes. A universal rolling ball is movably connected below the powder collection box to support the powder collection box. The universal rolling ball is embedded in a hemispherical hole of appropriate size processed on the bottom plate of the waste powder collection device shell. The powder screening mechanism realizes the powder screening function through the reciprocating drive of the powder screening drive assembly.

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