Blisk 3D printing and hot isostatic pressing densification preparation method and grinding device

Abstract

The invention provides a blisk 3D printing and hot isostatic pressing densification preparation method and a grinding device, belongs to the field of blisk manufacturing, and aims at solving the problems that in the prior art, a blisk is provided with more holes through 3D printing manufacturing, the blisk forming and spraying processes are independent, and the part process is tedious. The preparation method comprises the following steps: printing a blisk printing blank; the blisk printing blank is subjected to surface shot blasting treatment; spraying treatment is conducted, a functional coating is formed on the surface, and a blisk spraying blank is obtained; putting the blank into hot isostatic pressing equipment, and carrying out hot isostatic pressing treatment by taking the coating as a hot isostatic pressing sheath to obtain a compact blank of the blisk; and carrying out finish machining to obtain a blisk finished product. The blisk is prepared through 3D printing, the sprayed coating serves as a sheath for transmitting pressure to be subjected to densification treatment, the problem that the sheath is difficult to machine in a traditional process is avoided, the porosity of 3D printing parts can be reduced, and the densified blisk with excellent comprehensive performance is obtained.

Description

Technical Field

[0001] The present invention belongs to the field of integral blade disk manufacturing, and in particular relates to an integral blade disk 3D printing and hot isostatic pressing densification preparation method and a grinding device. Background Art

[0002] The traditional processing methods of the integral blade disk for aircraft engines have certain difficulties in processing due to its complex structure and high performance requirements. In recent years, 3D printing has been used to prepare integral blade disks, but the 3D printed parts themselves have many pores, some of which are connected to the outside world, and it is still impossible to ensure that all pores are closed after subsequent processing.

[0003] At the same time, aircraft engine blades need to use different coatings to achieve their corresponding functions according to different working temperatures and working environments. In the traditional manufacturing method, the overall blade molding and functional coating spraying are two independent steps. The parts process is cumbersome, the production cycle is long, and the coating is easy to fall off, causing the overall part to fail. Summary of the invention

[0004] In view of the shortcomings of the prior art mentioned above, the purpose of the present invention is to provide an integral blade disk 3D printing and hot isostatic pressing densification preparation method and grinding device, which is used to solve the problems in the prior art that the integral blade disk is manufactured by 3D printing with a large number of pores, the integral blade disk molding and spraying processes are independent, and the parts processing is cumbersome.

[0005] To achieve the above-mentioned purpose and other related purposes, the present invention provides a method for preparing an integral blade disk by 3D printing and hot isostatic pressing densification and a grinding device.

[0006] Among them, the integral blade disk 3D printing and hot isostatic pressing densification preparation method includes: Printing preparation steps: import the 3D model of the integral blade disk into the 3D printing layered slice processor and obtain the slice file; Printing step: importing the slice file into a selective laser melting additive manufacturing device for printing and obtaining an integral blade disk print blank; Shot peening step: performing a surface shot peening treatment on the printed integral blade disc blank, and then cleaning and drying the surface to obtain a shot peened integral blade disc blank; Spraying step: spraying the integral blade disc shot peening blank to form a functional coating on the surface to obtain an integral blade disc spray blank; Densification step: placing the integral blade disk spray blank into a hot isostatic pressing device, performing hot isostatic pressing treatment with the functional coating as a hot isostatic pressing jacket, and obtaining an integral blade disk dense blank; Finishing step: finishing the surface of the dense blank of the integral blade disk to obtain a finished integral blade disk.

[0007] Optionally, in the printing step, the powder raw material of the integral blade disk printed by the selective laser melting additive manufacturing equipment is titanium alloy or high temperature alloy or ceramic-based composite material; In the spraying step, the coating material is nickel, cobalt-based high-temperature alloy or high-performance composite material.

[0008] Optionally, in the printing step, the process parameters set for the selective laser melting additive manufacturing equipment are: laser power of 200-500W, scanning rate of 1000mm / s, powder layer thickness of 20-50μm, laser spot size of 50-100μm, and preheating temperature of 200°C.

[0009] Optionally, in the densification step, the hot isostatic pressing process includes vacuum degassing, heating to 800-1200° C., pressurizing to 100-150 MPa, and maintaining constant temperature and pressure for 2-4 hours.

[0010] Optionally, in the finishing step, the finishing process includes installing the integral blade disc compact blank in a CNC machine tool, grinding the body surface and blade top of the integral blade disc, and during the grinding process, the linear speed of the grinding wheel is 90-120m / s, the grinding depth is 0.01-0.02mm, the longitudinal feed speed is 5mm / min, and water machine coolant is used for cooling and lubrication.

[0011] Optionally, a blade surface grinding step is also included between the shot peening step and the spraying step.

[0012] The integral blade disc grinding device is used to perform the blade surface grinding steps as described above, including: Caps and grinding components; A rotating shaft is vertically arranged in the middle of the support platform, and the integral blade disk is detachably fixedly connected to the rotating shaft. A power source for driving the rotating shaft to drive the integral blade disk to rotate is arranged in the support platform; The grinding components include at least one group, and when there are more than one group of grinding components, they are arranged in a circular array around the rotation axis; The grinding assembly is slidably arranged on the surface of the support platform, and the sliding direction is along the radial direction of the rotating shaft. During the sliding process, it enters or leaves the blade area of ​​the integral blade disk, and grinds the blade surface after entering.

[0013] Optionally, the grinding assembly includes an upper plate body, a lower plate body, a first supporting assembly, a second supporting assembly and a grinding portion; The upper plate body and the lower plate body are respectively located at the top and bottom ends of the blades of the integral blisk, and the lower plate body is slidably matched with the support platform; The first support assembly includes an upper screw rod, a lower screw rod, a telescopic rod, a ball joint seat and an air cushion, and also includes an upper slide groove and a lower slide groove respectively arranged on the upper plate body and the lower plate body; On the upper plate body, the upper slide groove is located between the upper edges of two adjacent blades, and on the lower plate body, the lower slide groove is located between the lower edges of two adjacent blades; A plurality of the ball joint seats are connected in a linear array to form a ball joint seat row, two groups of the ball joint seat rows are slidably disposed in the upper slide groove and the lower slide groove respectively, the two groups of the ball joint seat rows are respectively penetrated and matched by the upper screw rod and the lower screw rod, and are driven by the screw rod to slide in the upper slide groove and the lower slide groove; Both ends of the plurality of telescopic rods are respectively connected to the two sets of ball joint seat rows through ball joints, and during the sliding process of the ball joint seat rows, the length and angle of each telescopic rod are automatically changed; The air cushion is an inflatable flexible bag, one side of which is fixedly connected to the plurality of telescopic rods, and when inflated, the other side of which clings to and supports one side surface of the blade; The second support assembly has the same structure as the first support assembly, but is separated from the first support assembly by two blades, and an air cushion is arranged on the other side of the plurality of telescopic rods, and the two air cushions are arranged opposite to each other; The grinding part is located between two middle blades and grinds the blades.

[0014] Optionally, a third support assembly is further provided between the first support assembly and the second support assembly, and the third support assembly is located between two blades. The third support assembly has the same structure as the first support assembly and the second support assembly, but air cushions are provided on both sides of the telescopic rod of the third support assembly, and the air cushions on both sides face the blades on both sides respectively; The grinding part has two groups, which are respectively arranged on both sides of the third support assembly. The grinding part includes an upper roller, a lower roller and a grinding belt. The upper roller and the lower roller both have rotational power. The upper roller is located on the upper side of the upper plate body, and the lower roller is located on the lower side of the lower plate body. The two ends of the grinding belt are respectively wound and fixed on the upper roller and the lower roller. The unfolded section of the grinding belt is located between the blade and the air cushion of the third support assembly. The upper roller or the lower roller is in a tapered shape with a gradually increasing cross section, and the end facing the rotating shaft is a small end.

[0015] Optionally, an equipment cabin is provided on the outer side of the lower plate body; Each group of upper rollers or lower rollers is provided with a driving mechanism, and the driving mechanism includes a driving wire shaft, a guide light shaft and a bracket sheet; The drive wire shaft and the guide light shaft are parallel to the axis of the upper roller or the lower roller. The drive wire shaft has a drive mechanism at one end of the equipment cabin, and the other end extends to the proximal end of the upper roller or the lower roller. The guide light shaft is fixed at one end of the equipment cabin, and the other end extends to the distal end of the upper roller or the lower roller. A bracket piece is rotatably installed at each end of the upper roller or the lower roller, the bracket piece at the distal end cooperates with the end of the guide light axis and the distal end of the upper roller or the lower roller respectively, the bracket piece at the proximal end cooperates with the guide light axis, the driving wire axis and the proximal end of the upper roller or the lower roller respectively, and the bracket piece at the proximal end is provided with a driving motor for rotating the upper roller or the lower roller.

[0016] As described above, the 3D printing and hot isostatic pressing densification preparation method and grinding device of the present invention have at least the following beneficial effects: The integral blade disk prepared by 3D printing technology can prepare parts with complex shapes and structures, achieve a perfect combination of high precision and complexity, and significantly improve material utilization, greatly shorten the production cycle, and reduce manufacturing costs. In addition, the coating is sprayed on the surface of the integral blade disk, and the coating is used as a hot isostatic pressing sleeve. The integral blade disk with the coating is placed in the hot isostatic pressing equipment for hot isostatic pressing. The obtained integral blade disk not only has low internal porosity and dense structure, but also has a layer of high-performance coating on the surface. The prepared integral blade disk has many excellent properties such as high strength, high toughness, and high corrosion resistance. Using the sprayed coating as a sleeve for transmitting pressure not only avoids the problems of difficult processing of the traditional process sleeve and cumbersome sleeve removal process, but also can make the through hole of the traditional 3D printing become a closed hole and then closed by hot isostatic pressing, which greatly reduces the porosity of the 3D printed parts and obtains a dense integral blade disk with excellent comprehensive performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 Shown is an overall schematic diagram of the present invention.

[0018] Figure 2 The schematic diagram of the present invention is shown as having only a single grinding assembly.

[0019] Figure 3 It is a schematic diagram of the first supporting assembly and the second supporting assembly of the present invention.

[0020] Figure 4 Shown is a schematic diagram of an air cushion on a support assembly of the present invention.

[0021] Figure 5 Shown is a schematic diagram of each support assembly and one group of grinding parts of the present invention.

[0022] Figure 6 Shown is an overall schematic diagram of the grinding assembly of the present invention.

[0023] Figure 7 Shown is a schematic diagram of driving the upper roller and the lower roller of the present invention.

[0024] Figure 8 Shown is a schematic diagram of the position of the grinding belt of the present invention during operation.

[0025] Among them: supporting platform 1, rotating shaft 10, grinding assembly 2, upper plate body 20, upper slide groove 201, lower slide groove 202, lower plate body 30, first support assembly 40, upper screw rod 401, lower screw rod 402, telescopic rod 403, ball joint seat row 404, air cushion 44, second support assembly 50, third support assembly 60, upper roller 701, lower roller 702, grinding belt 703, equipment cabin 80, drive wire shaft 801, guide light shaft 802, bracket plate 803, drive motor 804. DETAILED DESCRIPTION

[0026] The following is a description of the implementation of the present invention by means of specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0027] See also Figures 1 to 8 . It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings of this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change in the proportional relationship, or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the effects and purposes that can be achieved by the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. Changes or adjustments in their relative relationships should also be regarded as the scope of the implementation of the present invention without substantially changing the technical content.

[0028] The following embodiments are only for illustration purposes and can be combined with each other, and are not limited to the contents presented in the following single embodiments.

[0029] For an embodiment of the 3D printing and hot isostatic pressing densification preparation method and grinding device provided by the present invention, please refer to Figure 1-Figure 8 .

[0030] Among them, the integral blade disk 3D printing and hot isostatic pressing densification preparation method includes: Printing preparation steps: Import the 3D model of the whole blade disk into the 3D printing layered slice processor and obtain the slice file. Generally speaking, the manufacturer of the printing equipment will provide the matching 3D model slice processor software. After the whole blade disk model is imported into the software, it can automatically perform layered slices and generate slice files based on the layered slice results. The slice file includes slice outlines, slice thickness, printing instructions, support structure information, etc. In general, this step is consistent with the conventional 3D printing preparation process; Printing step: import the slice file into the selective laser melting additive manufacturing equipment to print and obtain the printed blank of the integral blade disk. In this step, the laser melting additive manufacturing equipment (also called laser selective melting equipment) can print out the initial blank of the integral blade disk according to the printing instructions and other information in the slice file; Shot peening steps: The surface of the printed integral blade disc is shot peened, and then cleaned and dried to obtain a shot peened integral blade disc. The shot peening process is a strengthening method that uses high-speed projectiles to strongly impact the surface of parts, causing deformation and hardening layers, and introducing residual stress. This process can significantly improve the workpiece's resistance to bending fatigue, stress corrosion fatigue, micro-wear and pitting corrosion. It is widely used in the matting and descaling of metal surfaces, improving the mechanical strength, fatigue resistance, wear resistance and corrosion resistance of parts, and eliminating residual stress of castings, forgings and welds. Shot peening does not change the chemical composition of the workpiece substrate, but only improves the surface structure. Before shot peening, clamp the blade disc on the shot peening equipment to avoid movement during the shot peening process, select steel shot as the shot peening medium, set the parameters of the shot peening medium and the shot peening time, and start the shot peening equipment. The integral blade disc needs to be cleaned and dried after shot peening; Spraying step: spray the integral blade disc shot peening blank to form a functional coating on the surface to obtain an integral blade disc spray blank, whose surface has a functional coating of a certain thickness. In order to achieve sufficient bonding strength, thermal spraying technologies such as plasma spraying, arc spraying, explosion spraying, and supersonic flame spraying can be used to prepare a coating on the surface of the integral blade disc. The composition of the coating can be selected according to the working scene of the integral blade disc. "Functional coating" refers to a coating with specific functions, such as high temperature resistance. Taking plasma arc spraying as an example, according to the type and function of the coating to be sprayed, select a suitable powder material. Then load the selected spray material into the powder feeder of the spray gun, and connect the spray gun to the power supply, gas source and other equipment. Set the spray parameters, aim the spray gun at the surface of the workpiece, start the power supply and gas source, and generate a plasma arc with the spray gun. The plasma arc heats the spray material to a molten or semi-molten state, and sprays it onto the surface of the workpiece at high speed to form a coating with good density and high bonding strength. Specifically, the set process parameters can be: spraying power is 35-42kW, spraying distance is 100-150mm, argon flow rate is 30-60L / min, and hydrogen flow rate is 5-15L / min; Densification step: Place the sprayed integral blade disc blank into the hot isostatic pressing equipment, and perform hot isostatic pressing with the functional coating as the hot isostatic pressing cover to obtain a dense integral blade disc blank. The "hot isostatic pressing" process is to place the product in a closed container, and use an inert gas as a pressure transmission medium under high temperature and high pressure to densify the material, thereby eliminating internal defects and improving wear resistance, corrosion resistance and mechanical properties. In the previous step of this step, the surface of the integral blade disc blank was sprayed to form a functional coating on the surface. In this step, the sprayed coating is used as a hot isostatic pressing cover, which covers the surface of the integral blade disc blank. The coating material can better serve as a cover for transmitting pressure through hot isostatic pressing; Finishing step: Finish the surface of the blisk compact blank to obtain the finished blisk. Specifically, the obtained blisk blank is mounted on the CNC machine tool, the running program instructions are set, and the surface of the blisk and the top of the blade are ground with high precision. After the top is processed, the blisk is turned over to process the bottom surface.

[0031] The beneficial effects of the above-mentioned integral blade disk preparation method are remarkable, and the integrated molding and high-quality preparation of the integral blade disk are realized. By combining 3D printing with hot isostatic pressing densification technology, not only the problem of many pores in 3D printed parts is solved, but also the one-time molding of the blade disk body and the blades is realized, which greatly simplifies the production process. What is particularly innovative is that the use of functional coating as hot isostatic pressing cover not only improves the performance of the blade disk surface, but also ensures the uniform transmission of pressure during hot isostatic pressing, further improving the quality and strength of the finished parts. In addition, this preparation method not only simplifies the processing process, but also strengthens the coating effect through hot isostatic pressing, avoiding the problem of easy detachment of the coating in traditional methods, significantly shortening the production cycle, and improving production quality. It has significant advantages in the field of integral blade disk preparation, and provides high-quality and high-strength integral blade disk solutions for high-end fields such as aircraft engines.

[0032] Furthermore, in the printing step of the above embodiment, the powder raw material of the selective laser melting additive manufacturing equipment for printing the integral blade disk printing blank is titanium alloy or high-temperature alloy or ceramic-based composite material. Titanium alloy powder is a tiny particle made of titanium alloy; high-temperature alloy powder refers to alloy powder that can maintain excellent mechanical properties and anti-oxidation and anti-corrosion capabilities at high temperatures, which mainly includes three types: nickel-based, cobalt-based and iron-based; ceramic-based composite material powder is a powder composed of a ceramic matrix and reinforcing materials such as high-strength and high-elasticity fibers. It has excellent properties such as high temperature resistance, high strength, high stiffness, and corrosion resistance, while overcoming the brittle weakness of ceramic materials.

[0033] In the spraying step, the coating material is a nickel- or cobalt-based high-temperature alloy or a high-performance composite material. Nickel-based high-temperature alloys are based on nickel and usually contain relatively high levels of chromium, molybdenum, tungsten and other elements, and have good high-temperature strength, oxidation resistance and corrosion resistance; cobalt-based high-temperature alloys are based on cobalt and usually contain chromium, nickel, tungsten and other elements, and have excellent high-temperature strength, wear resistance and thermal fatigue resistance; high-performance composite material coatings are usually composed of a variety of materials, such as ceramic-based composite materials, metal-based composite materials, etc. These materials have certain strength, wear resistance, high-temperature oxidation resistance and certain plasticity. As coating materials, they can make the sprayed coating better serve as a sheath for hot isostatic pressing to transfer pressure.

[0034] Titanium alloy, high temperature alloy and ceramic-based composite materials are used as the blade body, and nickel, cobalt-based high temperature alloy or high-performance composite materials are used as the surface spraying material. Their common characteristics are high temperature resistance, high strength and good corrosion resistance. When used on the integral blade of an aircraft engine, these materials can significantly improve the heat resistance, wear resistance and service life of the blade, while reducing weight, improving fuel efficiency, and ensuring the stable operation of the aircraft engine in a high temperature and high speed environment.

[0035] Furthermore, in the printing step of the above embodiment, the process parameters set by the selective laser melting additive manufacturing equipment are: laser power of 200-500W, scanning rate of 1000mm / s, powder layer thickness of 20-50μm, laser spot size of 50-100μm, and preheating temperature of 200℃. Specifically, the printing substrate is installed on the printing platform of the laser selective melting equipment. Usually, the same or similar material as the printing material is used. The substrate needs to be cleaned and preheated to ensure good bonding with the first layer of powder. The powder spreading system of the laser selective melting equipment will evenly spread a thin layer of metal powder on the substrate, and the thickness of the powder layer is consistent with the powder layer thickness set in the slicing file. The laser system selectively laser melts the powder layer according to the set parameters and paths. During printing, inert gases such as argon need to be introduced as protective gases to prevent oxidation. After completing a layer of printing, the printing platform drops a layer thickness, the powder spreading system spreads powder again, and the laser system continues to scan and melt, and the cycle repeats until the printing is completed to obtain an integral blade disk.

[0036] Furthermore, in the densification step of the above embodiment, the hot isostatic pressing process includes vacuum degassing, heating to 800-1200° C., pressurizing to 100-150 MPa, and maintaining constant temperature and pressure for 2-4 hours.

[0037] More specifically, after placing the entire blade disk in the pressure vessel of the hot isostatic pressing equipment, it is evacuated and then an inert gas such as argon is introduced into the pressure vessel as a pressure transmission medium. The inert gas can evenly transfer the pressure to the blade disk and maintain chemical stability at high temperatures. Start the hot isostatic pressing equipment, heat and pressurize the pressure vessel. The heating and pressure increase speeds must not be too fast to prevent the blade disk from deforming. After reaching the set temperature and pressure, maintain them for a period of time to allow the blade disk to further densify under the action of high temperature and high pressure. After the insulation and pressure are completed, stop heating and allow the blade disk to cool naturally in the pressure vessel, which will help the blade disk gradually release the stress generated under the action of high temperature and high pressure, thereby reducing the internal stress and deformation risk of the blade disk.

[0038] Furthermore, in the finishing step of the above embodiment, the finishing process includes installing the integral blade disc compact blank in a CNC machine tool, grinding the body surface and blade top of the integral blade disc, and during the grinding process, the linear speed of the grinding wheel is 90-120m / s, the grinding depth is 0.01-0.02mm, the longitudinal feed speed is 5mm / min, and water machine coolant is used for cooling and lubrication.

[0039] In the prior art, the Ti6Al4V blade disk for aircraft engines has certain difficulties in processing due to its complex structure and high performance requirements. Although 3D printing has been used to prepare integral blade disks in recent years, the 3D printed parts themselves have many pores, some of which are connected to the outside world, and it is still impossible to ensure that all pores are closed after subsequent processing. If a sleeve is used for hot isostatic pressing, the overall part can be densified, but due to the complex curved surface of the blade disk, the sleeve is difficult to process, and the process of removing the special-shaped sleeve is cumbersome.

[0040] At the same time, aircraft engine blades require different coatings to achieve their corresponding functions according to different working temperatures and working environments. In traditional manufacturing methods, overall blade forming and functional coating are two independent steps. The parts process is cumbersome, the production cycle is long, and it is easy to fall off, causing the overall parts to fail.

[0041] This solution is aimed at many problems existing in the processing of Ti6Al4V blades for aircraft engines, such as the many pores in traditional 3D printed parts. Even if the cover is used for hot isostatic pressing, the complex curved surface of the blades makes the cover difficult to process and the removal process cumbersome. Another example is the traditional production method, in which the integral blade is formed and the functional coating is carried out in steps, the process is cumbersome, the production cycle is long, and the coating is easy to fall off, affecting the overall performance of the parts. This solution innovatively prepares the integral blade through 3D printing, and uses the spray coating directly as the cover for hot isostatic pressing. It not only simplifies the process steps, but also successfully solves the technical problems of the integral blade having many pores and complex shapes that are difficult to densify using the cover, significantly improving the quality and performance of the blade.

[0042] In the above embodiment, between the shot peening step and the spraying step, there is also a blade surface grinding step. Shot peening will form tiny marks and a compressive stress layer on the blade surface to improve its fatigue resistance, but this process will also make the surface rough; while the grinding step can reduce the surface roughness caused by shot peening, making the blade surface smoother, providing a better base for the subsequent spraying step, and ensuring that the coating can be evenly attached to the blade surface. The grinding step should be performed as soon as possible after the shot peening step, and the spraying step should be performed as soon as possible after the grinding step to avoid the surface that has just been shot peened or ground from being exposed to the air for a long time.

[0043] Please refer to the attached Figure 1-Figure 8 The integral blade disc grinding device is used to perform the above blade surface grinding steps, including: The base 1 and the grinding assembly 2 are barrel-shaped as a whole. When operating, side walls and a top plate are set to isolate the working area. Figure 1 Only the side perimeter is indicated; A rotating shaft 10 is vertically arranged in the middle of the support 1, and the integral blade disc is detachably fixedly connected to the rotating shaft 10. A power source for driving the rotating shaft 10 to drive the integral blade disc to rotate is arranged in the support 1. The integral blade disc can be loaded into the rotating shaft 10 from top to bottom and fixedly connected to it. After the grinding operation is completed, the integral blade disc can be removed and replaced; There is at least one group of grinding assemblies 2. When there are more than one group of grinding assemblies 2, they are arranged in a circular array around the rotating shaft 10, so that multiple blades can be ground at the same time. The grinding assembly 2 is slidably disposed on the surface of the support platform 1, and the sliding direction is along the radial direction of the rotating shaft 10. During the sliding process, the grinding operation part can enter or leave the blade area of ​​the integral blade disk, and grind the blade surface after entering.

[0044] The main working process of the above device is as follows: the grinding assembly 2 slides away from the rotating shaft 10 on the support to make room, the integral blade disc is installed into the rotating shaft 10 from top to bottom and is fixedly connected thereto, the grinding assembly 2 slides toward the rotating shaft 10 on the support, and the grinding operation part of the grinding assembly 2 enters the blade area of ​​the integral blade disc and grinds the specific blade. After the grinding of the current blade is completed, the grinding assembly 2 retreats and leaves the blade area of ​​the integral blade disc, the rotating shaft 10 drives the integral blade disc to rotate a specific angle and then fixes it, and the grinding assembly 2 enters the blade area of ​​the integral blade disc again and grinds the new blade. This cycle is repeated until all blades are ground. Remove and replace the integral blade disc.

[0045] For further information, see Figure 3 The grinding assembly 2 includes an upper plate body 20, a lower plate body 30, a first support assembly 40, a second support assembly 50 and a grinding part. Figure 3 The grinding part is not shown; The upper plate 20 and the lower plate 30 are respectively located at the top and bottom of the blade of the integral blade disk, and the lower plate 30 is slidably matched with the support 1. When the grinding assembly 2 slides to the innermost position on the support toward the rotating shaft 10, the upper plate 20 and the lower plate 30 clamp the upper and lower sides of the blade area of ​​the integral blade disk, but do not contact the blades. Figure 5 ; The first support assembly 40 includes an upper screw rod 401, a lower screw rod 402, a telescopic rod 403, a ball joint seat and an air cushion 44, and also includes an upper slide groove 201 and a lower slide groove 202 respectively arranged on the upper plate body 20 and the lower plate body 30; On the upper plate body 20, the upper slide groove 201 is located between the upper edges of two adjacent blades, and on the lower plate body 30, the lower slide groove 202 is located between the lower edges of two adjacent blades; A plurality of ball joint seats are connected in a linear array to form a ball joint seat row 404. Two sets of ball joint seat rows 404 are slidably disposed in the upper slide groove 201 and the lower slide groove 202, respectively. The two sets of ball joint seat rows 404 are respectively penetrated by the upper screw rod 401 and the lower screw rod 402, and are driven by the screw rod to slide in the upper slide groove 201 and the lower slide groove 202; Both ends of the multiple telescopic rods 403 are connected to two sets of ball joint seat rows 404 through ball joints, and during the sliding process of the ball joint seat rows 404, the length and angle of each telescopic rod 403 are automatically changed; The air cushion 44 is an inflatable flexible bag, one side of which is fixedly connected to the multiple telescopic rods 403, and when inflated, the other side of the air cushion 44 is closely attached to and supports one side surface of the blade; The second support assembly 50 has the same structure as the first support assembly 40, but is separated from the first support assembly 40 by two blades, and the air cushion 44 is arranged on the other side of the multiple telescopic rods 403, and the two air cushions 44 are arranged opposite to each other; The grinding part is located between the two middle blades and grinds the blades.

[0046] In the above embodiment, the main working process is as follows: before the grinding assembly 2 enters the blade area of ​​the integral blade disk to prepare for grinding the blade, the upper plate body 20 and the lower plate body 30 first enter the upper and lower parts of the blade, and then the first support assembly 40 and the second support assembly 50 are driven by the rotation of the upper screw rod 401 and the lower screw rod 402, and the ball joint seat row 404 carries the air cushion 44 to enter between the blades. Figure 3 and Figure 4 After the air cushion 44 enters between the blades, it is inflated. After the air cushion expands, it supports one side of the blade, and then the grinding part can grind the other side of the blade. Due to the supporting effect of the air cushion, the local area of ​​the blade is not easily deformed when subjected to the grinding force, thereby maintaining the shape and position accuracy of the blade. Even when manually grinding with sandpaper, it still has a supporting effect, reducing the difficulty of the grinding operation.

[0047] In the above embodiment, the reason why the first support assembly 40 and the second support assembly 50 enter the blade area is due to the shape of the blade, which can be seen in Figure 5 , the blades are twisted surfaces in different rows, and the first support component 40 can neither be directly inserted between the two blades from top to bottom nor inserted between the two blades from outside to inside in the horizontal plane. In this regard, in the present embodiment, each support component is specially configured, and the upper and lower parts of the support component are inserted between the two blades in different directions. The telescopic rod 403 whose length and angle can be independently changed is used to adapt to the distance and angle difference between the upper and lower parts of the support component due to different entry angles, so that the air cushion 44 is sent between the blades and fixed, and the expansion of the air cushion 44 automatically fills the distance between the support component, the upper plate body 20 and the lower plate body 30 and the blades to form support for the blades. The shape of the air cushion 44 can be designed according to the shape of the blade, and the expansion direction of the air cushion 44 can be controlled according to the wall thickness. The area with a small wall thickness of the air cushion 44 expands earlier than the area with a large wall thickness.

[0048] This embodiment can be found in Figure 5 A third support assembly 60 is further provided between the first support assembly 40 and the second support assembly 50. The third support assembly 60 is located between the two blades. The third support assembly 60 has the same structure as the first support assembly 40 and the second support assembly 50, but air cushions 44 are provided on both sides of the telescopic rod 403 of the third support assembly 60, and the air cushions 44 on both sides face the blades on both sides respectively; There are two groups of grinding parts, which are respectively arranged on both sides of the third support assembly 60. Figure 5 Only the left grinding part is shown, and the grinding part includes an upper roller 701, a lower roller 702 and a grinding belt 703. The upper roller 701 and the lower roller 702 are both powered by rotation. The upper roller 701 is located on the upper side of the upper plate 20, and the lower roller 702 is located on the lower side of the lower plate 30. The two ends of the grinding belt 703 are respectively wound and fixed on the upper roller 701 and the lower roller 702. The unfolded section of the grinding belt 703 is located between the blade and the air cushion 44 of the third support assembly 60. The upper roller 701 or the lower roller 702 is in a tapered shape with a gradually increasing cross section, and the end facing the rotating shaft 10 is a small end.

[0049] In the above embodiment, when the air cushion 44 of the third support assembly 60 is inflated, it can squeeze the grinding belt 703 to make it close to the surface of the blade. When the upper roller 701 and the lower roller 702 rotate back and forth to drive the grinding belt 703 to move back and forth on the surface of the blade, the surface of the blade is ground. It should be noted that the shape of the blade is a twisted curved surface, and the shape and width of the inner and outer sides of the blade are different. In order to achieve the fitting effect of the grinding belt 703 on the blade surface, in addition to the supporting effect of the air cushion 44, the shape of the grinding belt 703 needs to be designed. The inner and outer widths of the grinding belt 703 should match the blade, that is, during the grinding process, the grinding belt 703 should have the same linear speed at all points where it contacts the blade. Blades of different shapes may require different grinding belt 703 shapes to be designed to match the blade surface. Figure 5 For example, the grinding belt 703 is unfolded into a fan-shaped shape. In order to allow the upper roller 701 and the lower roller 702 to drive the grinding belt 703 to grind the blades back and forth, the upper roller 701 and the lower roller 702 are matched with cones.

[0050] In this embodiment, an equipment compartment 80 is provided on the outer side of the lower plate body 30. Figure 1 As shown, the drive and control mechanisms of each shaft are arranged in the equipment compartment 80 for easy maintenance; Each set of upper rollers 701 or lower rollers 702 is provided with a driving mechanism, which includes a driving wire shaft 801, a guide light shaft 802 and a bracket sheet 803; The drive wire shaft 801 and the guide light shaft 802 are parallel to the axis of the upper roller 701 or the lower roller 702. The drive wire shaft 801 has a drive mechanism at one end of the equipment cabin 80, and the other end extends to the proximal end of the upper roller 701 or the lower roller 702. The guide light shaft 802 is fixed at one end of the equipment cabin 80, and the other end extends to the distal end of the upper roller 701 or the lower roller 702. A bracket piece 803 is rotatably installed at both ends of the upper roller 701 or the lower roller 702. The bracket piece 803 at the distal end cooperates with the end of the guide light axis 802 and the distal end of the upper roller 701 or the lower roller 702 respectively, and the bracket piece 803 at the proximal end cooperates with the guide light axis 802, the driving wire axis 801 and the proximal end of the upper roller 701 or the lower roller 702 respectively. A driving motor 804 is provided on the proximal bracket piece 803 for rotating the upper roller 701 or the lower roller 702.

[0051] In the above embodiment, the driving mechanism can drive the upper roller 701 and the lower roller 702 to move radially along the blade disk so as to bring the grinding belt 703 into and out of the blade area, and can also drive the upper roller 701 and the lower roller 702 to rotate to grind the blade. The axis direction of the upper roller 701 and the lower roller 702 should be consistent with the sliding direction of the corresponding support assembly.

[0052] In summary, the present invention effectively overcomes various shortcomings in the prior art, can produce beneficial technical effects, and has significant progress.

[0053] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. The method for preparing a blisk by 3D printing and hot isostatic pressing densification is characterized in that: include: Printing preparation steps: import the 3D model of the integral blade disk into the 3D printing layered slice processor and obtain the slice file; Printing step: importing the slice file into a selective laser melting additive manufacturing device for printing and obtaining an integral blade disk print blank; Shot peening step: performing a surface shot peening treatment on the printed integral blade disc blank, and then cleaning and drying the surface to obtain a shot peened integral blade disc blank; Spraying step: spraying the integral blade disc shot peening blank to form a functional coating on the surface to obtain an integral blade disc spray blank; Densification step: placing the integral blade disk spray blank into a hot isostatic pressing device, performing hot isostatic pressing treatment with the functional coating as a hot isostatic pressing jacket, and obtaining an integral blade disk dense blank; Finishing step: finishing the surface of the dense blank of the integral blade disk to obtain a finished integral blade disk.

2. The method for preparing a blisk by 3D printing and hot isostatic pressing densification according to claim 1, characterized in that: In the printing step, the powder raw material of the integral blade disk printed by the selective laser melting additive manufacturing equipment is titanium alloy or high temperature alloy or ceramic-based composite material; In the spraying step, the coating material is nickel, cobalt-based high-temperature alloy or high-performance composite material.

3. The method for preparing a blisk by 3D printing and hot isostatic pressing densification according to claim 1, characterized in that: In the printing step, the process parameters set by the selective laser melting additive manufacturing equipment are: laser power of 200-500W, scanning rate of 1000mm / s, powder layer thickness of 20-50μm, laser spot size of 50-100μm, and preheating temperature of 200°C.

4. The method for preparing a blisk by 3D printing and hot isostatic pressing densification according to claim 1, characterized in that: In the densification step, the hot isostatic pressing process includes vacuum degassing, heating to 800-1200° C., pressurizing to 100-150 MPa, and maintaining constant temperature and pressure for 2-4 hours.

5. The method for preparing a blisk by 3D printing and hot isostatic pressing densification according to claim 1, characterized in that: In the finishing step, the finishing process includes installing the dense blank of the integral blade disk in a CNC machine tool, grinding the body surface and the blade tip of the integral blade disk, and during the grinding process, the linear speed of the grinding wheel is 90-120m / s, the grinding depth is 0.01-0.02mm, the longitudinal feed speed is 5mm / min, and water machine coolant is used for cooling and lubrication.

6. The method for preparing a blisk by 3D printing and hot isostatic pressing densification according to claim 1, characterized in that: A blade surface grinding step is also included between the shot peening step and the spraying step.

7. An integral blade disc grinding device, used for performing the blade surface grinding step as claimed in claim 6, characterized in that: include: A support (1) and a grinding assembly (2); A rotating shaft (10) is vertically arranged in the middle of the support platform (1), and the integral blade disk is detachably fixedly connected to the rotating shaft (10), and a power source for driving the rotating shaft (10) to drive the integral blade disk to rotate is arranged in the support platform (1); The grinding components (2) include at least one group. When the grinding components (2) include more than one group, the grinding components (2) are arranged in a circular array around the rotating shaft (10); The grinding assembly (2) is slidably arranged on the surface of the support platform (1), and the sliding direction is along the radial direction of the rotating shaft (10). During the sliding process, it enters or leaves the blade area of ​​the integral blade disk, and grinds the blade surface after entering.

8. The blisk grinding device according to claim 7, characterized in that: The grinding assembly (2) comprises an upper plate body (20), a lower plate body (30), a first support assembly (40), a second support assembly (50) and a grinding portion; The upper plate body (20) and the lower plate body (30) are respectively located at the top and bottom ends of the blades of the integral blisk, and the lower plate body (30) is slidably matched with the support platform (1); The first support assembly (40) comprises an upper screw rod (401), a lower screw rod (402), a telescopic rod (403), a ball joint seat and an air cushion (44), and also comprises an upper slide groove (201) and a lower slide groove (202) respectively arranged on the upper plate body (20) and the lower plate body (30); On the upper plate body (20), the upper slide groove (201) is located in the middle of the upper edges of two adjacent blades, and on the lower plate body (30), the lower slide groove (202) is located in the middle of the lower edges of two adjacent blades; A plurality of the ball joint seats are connected in a linear array to form a ball joint seat row (404), two groups of the ball joint seat rows (404) are respectively slidably disposed in the upper slide groove (201) and the lower slide groove (202), the two groups of the ball joint seat rows (404) are respectively penetrated by the upper screw rod (401) and the lower screw rod (402), and are driven by the screw rod to slide in the upper slide groove (201) and the lower slide groove (202); Both ends of the plurality of telescopic rods (403) are respectively connected to two groups of ball joint seat rows (404) via ball joints, and during the sliding process of the ball joint seat rows (404), the length and angle of each telescopic rod (403) are automatically changed; The air cushion (44) is an inflatable flexible bag, one side of the air cushion (44) is fixedly connected to the plurality of telescopic rods (403), and when inflated, the other side of the air cushion (44) is closely attached to and supports one side surface of the blade; The second support assembly (50) has the same structure as the first support assembly (40), but is separated from the first support assembly (40) by two blades, and an air cushion (44) is arranged on the other side of the plurality of telescopic rods (403), and the two air cushions (44) are arranged opposite to each other; The grinding part is located between two middle blades and grinds the blades.

9. The blisk grinding device according to claim 8, characterized in that: A third support assembly (60) is further provided between the first support assembly (40) and the second support assembly (50), and the third support assembly (60) is located between the two blades. The third support assembly (60) has the same structure as the first support assembly (40) and the second support assembly (50), but air cushions (44) are provided on both sides of the telescopic rod (403) of the third support assembly (60), and the air cushions (44) on both sides face the blades on both sides respectively; The grinding part has two groups, which are respectively arranged on both sides of the third support assembly (60), and the grinding part comprises an upper roller (701), a lower roller (702) and a grinding belt (703). The upper roller (701) and the lower roller (702) both have rotational power. The upper roller (701) is located on the upper side of the upper plate body (20), and the lower roller (702) is located on the lower side of the lower plate body (30). The two ends of the grinding belt (703) are respectively wound and fixed on the upper roller (701) and the lower roller (702). The unfolded section of the grinding belt (703) is located between the blade and the air cushion (44) of the third support assembly (60); The upper roller (701) or the lower roller (702) is in the shape of a cone with a gradually increasing cross-section, with the end facing the rotating shaft (10) being a small end.

10. The blisk grinding device according to claim 9, characterized in that: An equipment cabin (80) is provided on the outer side of the lower plate body (30); Each group of the upper rollers (701) or the lower rollers (702) is provided with a driving mechanism, wherein the driving mechanism comprises a driving wire shaft (801), a guide light shaft (802) and a bracket sheet (803); The drive wire shaft (801) and the guide light shaft (802) are both parallel to the axis of the upper roller (701) or the lower roller (702); the drive wire shaft (801) has a drive mechanism at one end of the equipment cabin (80) and the other end extends to the proximal end of the upper roller (701) or the lower roller (702); the guide light shaft (802) is fixed at one end of the equipment cabin (80) and the other end extends to the distal end of the upper roller (701) or the lower roller (702); A support piece (803) is rotatably mounted on each of the two ends of the upper roller (701) or the lower roller (702); the support piece (803) at the distal end cooperates with the distal end of the guide light axis (802) and the distal end of the upper roller (701) or the lower roller (702), respectively; the support piece (803) at the proximal end cooperates with the guide light axis (802), the drive wire axis (801) and the proximal end of the upper roller (701) or the lower roller (702), respectively; and a drive motor (804) is provided on the support piece (803) at the proximal end for rotating the upper roller (701) or the lower roller (702).

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