A method for removing support of laser additive manufacturing of thin-walled special-shaped curved surface parts and its application and support removal auxiliary device

Abstract

The present application relates to the field of additive manufacturing, in particular to a kind of support removal method for laser additive manufacturing thin-walled special-shaped curved surface parts and its application and support removal auxiliary device.The removal method described in the present application forms a support removal auxiliary device by manufacturing a conformal main structure and a water cooling device, and simultaneously cools the part by air and liquid during the support removal process, reduces the temperature of the part, reduces thermal stress, can inhibit large size deformation of the part, and improves forming quality.At the same time, by designing the shape and size of the support removal auxiliary device and the water cooling device, the function is fully exerted while the machining amount is minimized and the material used is minimized.Meanwhile, by designing the placement position of the part during laser selective melting additive manufacturing process, the support is only added to one side of the part, which better adapts to the removal method described in the present application.The present application reduces the deformation tendency of laser selective melting additive manufacturing parts and improves the forming quality.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of additive manufacturing, in particular to a support removal method for laser additive manufacturing of thin-walled special-shaped curved surface parts and application and support removal auxiliary device thereof. BACKGROUND

[0002] Thin-walled special-shaped curved surface parts have complex structures, and it is very difficult to prepare them by traditional casting, forging and other processes. Laser selective melting additive manufacturing technology adopts a layer-by-layer accumulation method for part manufacturing, and the forming process does not need to use a mold, which is very suitable for manufacturing thin-walled special-shaped curved surface parts. However, thin-walled special-shaped curved surface parts have poor structural rigidity and have difficult-to-form structures such as overhanging surfaces. Therefore, support structures need to be added to the parts during laser selective melting additive manufacturing to assist the forming process. After the part manufacturing is completed, the support loses its function and needs to be mechanically removed.

[0003] When the laser selective melting additive manufacturing thin-walled special-shaped curved surface part is removed from the support, the mechanical action between the tool and the part will cause the local temperature of the part to rise, forming a temperature gradient inside the part. Influenced by this, the thin-walled special-shaped curved surface part is prone to deformation or even cracking, resulting in part scrap and failure to meet the use requirements. Therefore, a laser selective melting additive manufacturing and support removal method for thin-walled special-shaped curved surface parts is needed to avoid deformation and cracking of the parts. SUMMARY

[0004] Therefore, the technical problem to be solved by the present application is to provide a support removal method for laser additive manufacturing of thin-walled special-shaped curved surface parts and application and support removal auxiliary device thereof. The removal method provided by the present application can simultaneously perform air cooling and water cooling on the part during support removal, reduce the temperature of the part, reduce thermal stress, inhibit large-size deformation of the part, and improve the forming quality.

[0005] The present application provides a support removal method for laser additive manufacturing of thin-walled special-shaped curved surface parts, comprising the following steps:

[0006] S1) providing a support removal auxiliary device, which comprises a main body structure 1 and a water cooling device 2;

[0007] The main body structure 1 comprises a first surface and a second surface, and is provided with a cooling gas channel communicating between the first surface and the second surface; the first surface matches the opposite surface of the surface where the support to be removed of the laser additive manufacturing thin-walled special-shaped curved surface part is located, so that the gas discharged from the cooling gas channel can cover the opposite surface of the surface where the support to be removed of the laser additive manufacturing thin-walled special-shaped curved surface part is located; the end surface of the main body structure 1 is provided with a water cooling device fixing mechanism 101, and the water cooling device fixing mechanism 101 is provided with a water cooling device interface 111;

[0008] The water cooling device 2 is internally provided with a cooling water channel 201; the water cooling device 2 is provided with a connecting column 202 matched with the water cooling device interface 111, so that the water cooling device 2 can be fixed on the end face of the main body structure 1 through the water cooling device fixing mechanism 101, and the surface of the water cooling device 2 can be attached to the opposite face of the face where the support to be removed of the laser additive manufacturing thin-walled special-shaped curved surface part is located;

[0009] S2) The surface of the water cooling device 2 of the support removal auxiliary device in step S1) is attached to the opposite face of the face where the support to be removed of the laser additive manufacturing thin-walled special-shaped curved surface part is located, while cooling gas is introduced into the cooling gas channel and cooling liquid is introduced into the cooling liquid channel, and the support to be removed of the laser additive manufacturing thin-walled special-shaped curved surface part is mechanically removed.

[0010] The support removal method for the laser additive manufacturing thin-walled special-shaped curved surface part provided by the application firstly provides a support removal auxiliary device, which comprises a main body structure 1 and a water cooling device 2. The main body structure 1 of the application is the functional entity of the gas cooling system of the support removal auxiliary device, which comprises a first surface and a second surface.

[0011] The first surface of the application matches the opposite face of the face where the support to be removed of the laser additive manufacturing thin-walled special-shaped curved surface part is located, so that the gas discharged from the cooling gas channel can cover the opposite face of the face where the support to be removed of the laser additive manufacturing thin-walled special-shaped curved surface part is located; specifically, the first surface is conformally matched with the opposite face of the face where the support to be removed of the part is located, so that any part of the first surface can correspond to the opposite face of the face where the support to be removed of the part is located, so that when the cooling gas is sprayed out from the first surface through the cooling gas channel, the cooling gas can cover and cool the opposite face of the face where the support to be removed of the part is located; the first surface of the support removal auxiliary device is conformally designed with the part, so that the cooling gas can fully cover the outer surface of the part during the support removal process, and the best cooling effect is achieved.

[0012] The main body structure 1 is provided with a cooling gas channel communicating the first surface and the second surface. Specifically, the main body structure 1 has a cavity 102 with a wall thickness of 5 mm to 10 mm inside, the first surface is provided with a through gas outlet hole 104, the second surface is provided with a through gas inlet hole 103, the gas outlet hole 104 and the gas inlet hole 103 communicate with the cavity 102 to form a cooling gas channel, so that the gas can enter from the gas inlet hole 103 and then be discharged from the gas outlet hole 104. If the wall thickness is too small, the overall rigidity of the cooling system is poor, and it is easy to be damaged during use, and the processing difficulty is large; if the wall thickness is too large, the amount of material is large, but the cooling effect is not obvious, under the premise of ensuring the cooling effect can fully play, the size and weight of the device are reduced as much as possible, and the processing material and time are saved.

[0013] The first surface of the main body structure 1 has a plurality of gas outlet hole arrays, preferably six gas outlet hole arrays, each gas outlet hole array is composed of 3x3 gas outlet holes 104, the center distance between adjacent two gas outlet holes 104 is 5 mm to 10 mm, and the center distance of the gas outlet hole 104 at the array center of the adjacent two gas outlet hole arrays is 20 mm to 40 mm. The purpose of such design is to use the least number of gas outlet holes 104 to achieve the maximum cooling effect, if the number of gas outlet holes 104 is too small and the distance is too large, the cooling effect is not good; if the number of gas outlet holes 104 is too large and the distance is too small, the processing period is prolonged, and more gas outlet holes 104 will cause the overall strength of the device to decrease.

[0014] The air outlet hole 104 is coaxially connected by a first flat-top conical hole section and a second flat-top conical hole section; the large end of the first flat-top conical hole section is communicated with the cavity 102, and the small end is coincided with the large end of the second flat-top conical hole section at the joint surface; the small end of the second flat-top conical hole section is directed to the first surface; the diameter of the large end surface of the first flat-top conical hole section is 3 mm-4 mm, the diameter of the small end surface of the first flat-top conical hole section is 1.5 mm-2.5 mm, and the length of the first flat-top conical hole section is 2 mm-4 mm; the diameter of the large end surface of the second flat-top conical hole section is 1.5 mm-2.5 mm, the diameter of the small end surface of the second flat-top conical hole section is 1 mm-2 mm, and the length of the second flat-top conical hole section is 3 mm-6 mm. The small end of the second flat-top conical hole section is directed to the first surface and penetrates the first surface, so that the air outlet hole communicates the cavity 102 inside the main body structure with the outside. It can be seen that the air outlet hole 104 is a funnel-shaped hole composed of two flat-top conical hole sections, and the shape and size of the air outlet hole 104 can make the internal cooling gas have a large flow rate when it is blown to the surface of the part to be processed, so that the cooling effect is better.

[0015] In the air outlet hole array, the central symmetry axes of the first flat-top conical hole sections of all the air outlet holes 104 are parallel to the normal direction of the surface where the large end is located; in the air outlet hole array, the angle between the central symmetry axis of the second flat-top conical hole section of one air outlet hole 104 at the center of the array and the central symmetry axis of the first flat-top conical hole section is 0°; in the air outlet hole array, the angle between the central symmetry axis of the second flat-top conical hole section of each of the four air outlet holes 104 at the four corners of the array and the central symmetry axis of the first flat-top conical hole section is 40°-60°; in the air outlet hole array, the angle between the central symmetry axis of the second flat-top conical hole section of each of the four air outlet holes 104 at the four sides of the array and the central symmetry axis of the first flat-top conical hole section is 30°-50°. The shape of the air outlet hole 104 can make the cooling gas blow to the surface of the part from different directions, so that the gas flow can fully cover the surface of the part, and the cooling effect is better.

[0016] The second surface of the main body structure is provided with two air inlet holes 103 arranged in the longitudinal direction; specifically, the second surface is provided with two air inlet holes 103 arranged in the longitudinal direction, respectively at the longitudinal edges of the second surface, that is, one air inlet hole 103 is at the top of the main body structure, and the other air inlet hole 103 is at the bottom of the main body structure, so that the air inlet holes 103 can make the cooling air fully fill the internal cavity of the support removal auxiliary device and form a positive pressure, achieving the best cooling effect. The diameter of the air inlet hole 103 is 10 mm to 15 mm; the diameter of the air inlet hole 103 is designed to reduce the amount of raw materials used while improving the cooling effect. If the diameter is too small, the air inlet amount is insufficient, and the cooling effect is not good; if the diameter is too large, more material needs to be processed, but the cooling effect is not significantly improved.

[0017] The end surface of the main body structure 1 is provided with a water cooling device fixing mechanism 101, and the water cooling device fixing mechanism 101 is provided with a water cooling device interface 111; specifically, the water cooling device fixing mechanism 101 is integrally formed with the main body structure 1, and the water cooling device fixing mechanism 101 is provided with a water cooling device interface 111 penetrating the water cooling device fixing mechanism 101. The water cooling device interface 111 is a through hole with an inner diameter of 11 mm to 20 mm, which can match the size of the water cooling device and facilitate subsequent assembly. The wall thickness of the water cooling device interface 111 is 3 mm to 5 mm; specifically, the thickness of the water cooling device interface 111 refers to the thickness between the inner diameter wall of the water cooling device interface 111 along the normal direction of the inner diameter wall and the outer surface of the water cooling device fixing mechanism 101; under the premise of ensuring the structural strength, the least amount of material can be used for processing.

[0018] The material of the main body structure 1 is preferably ceramic; ceramic has excellent strength, hardness and wear resistance, and is low in price. It can balance functionality and economy. The main body structure 1 of the present application is preferably manufactured by selective laser sintering technology. The main body structure 1 of the present application has complex and fine structures such as conformal surface and micropores, which are difficult to manufacture by traditional process, long cycle and high cost. Using selective laser sintering technology can complete the manufacturing with high efficiency, low cost and high quality.

[0019] The water cooling device 2 is used for water cooling the surface of the part in the support removing process, and is internally provided with a cooling water channel 201. Specifically, the water cooling device 2 is a conformal hollow pipeline in contact with the part, and is designed in a conformal structure so as to fully adhere to the surface of the part in the water cooling of the surface of the part in the support removing process, thereby achieving the best cooling effect. The wall thickness of the water cooling device 2 is 3 mm to 5 mm. Specifically, the wall thickness of the water cooling device 2 refers to the minimum distance between the wall of the cooling water channel 201 internally provided in the water cooling device 2 and the outer surface of the water cooling device 2. If the wall thickness is too small, the overall rigidity of the cooling system is poor, and the cooling system is prone to damage during use, and the processing difficulty is large. If the wall thickness is too large, the amount of material is large, but the cooling effect is not obviously contributed. Under the premise of ensuring that the cooling effect can fully play, the size and weight of the device are reduced as much as possible, and the processing material and time are saved.

[0020] The water cooling device 2 is provided with a connecting column 202 matched with the water cooling device interface 111, so that the water cooling device 2 can be fixed on the end surface of the main body structure 1 through the water cooling device fixing mechanism 101, and the surface of the water cooling device 2 can be attached to the opposite surface of the surface of the laser additive manufacturing thin-walled special-shaped curved surface part to be removed from the support. The outer diameter of the connecting column 202 matches the inner diameter of the water cooling device interface 111, so that the water cooling device 2 and the main body structure 1 can be firmly combined, and better processing effect can be achieved. The length of the connecting column 202 is the same as the through length of the water cooling device interface 111.

[0021] The diameter of the cooling water channel 201 is 5 mm to 10 mm. Such a design is to reduce the processing difficulty while improving the cooling effect. If the diameter is too small, the processing difficulty is large, and the small water flow will lead to poor cooling effect. If the diameter is too large, more cooling water is needed to fill the internal flow channel, but the cooling effect is not obviously improved. Considering the above factors, under the premise of ensuring that the part surface can be fully cooled, the size and weight are reduced as much as possible, the processing material and time are saved, and the manufacturing difficulty of the device is reduced.

[0022] The material of the water cooling device 2 is preferably copper alloy. The water cooling device 2 selects copper alloy as the material because copper alloy has good heat conductivity and can achieve good cooling effect. The water cooling device 2 is preferably manufactured by laser selective melting additive manufacturing technology. Because the water cooling device 2 has a conformal surface and an internal flow channel, it is difficult to manufacture by traditional process, the cycle is long, and the cost is high. The laser selective melting additive manufacturing technology can be used to complete the manufacturing with high efficiency and low cost.

[0023] The support removal method of the laser additive manufacturing thin-walled special-shaped curved surface part of the present application provides a support removal auxiliary device, and then the surface of the water cooling device 2 to be removed is attached to the opposite surface of the surface of the laser additive manufacturing thin-walled special-shaped curved surface part to be removed, and the cooling gas channel is supplied with cooling gas and the cooling liquid channel is supplied with cooling liquid, and the support to be removed of the laser additive manufacturing thin-walled special-shaped curved surface part is mechanically removed.

[0024] Specifically, when the water cooling device 2 is fixed on the end surface of the main body structure 1 and the surface of the water cooling device 2 is attached to the opposite surface of the surface of the laser additive manufacturing thin-walled special-shaped curved surface part to be removed, the first surface of the main body structure 1 is attached to the opposite surface of the surface of the laser additive manufacturing thin-walled special-shaped curved surface part to be removed, and the cooling gas channel is supplied with cooling gas and the cooling liquid channel is supplied with cooling liquid, so that the cooling gas covers the outer surface of the laser additive manufacturing thin-walled special-shaped curved surface part, and the cooling liquid and the outer surface of the laser additive manufacturing thin-walled special-shaped curved surface part exchange heat, and the support to be removed of the laser additive manufacturing thin-walled special-shaped curved surface part is mechanically removed.

[0025] The laser additive manufacturing thin-walled special-shaped curved surface part to which the removal method of the present application is applied includes opposite first and second special-shaped curved surfaces, and the support to be removed is arranged on the first or second special-shaped curved surface. If the support to be removed is arranged on the first special-shaped curved surface, the second special-shaped curved surface is the opposite surface of the surface of the laser additive manufacturing thin-walled special-shaped curved surface part to be removed. If the support to be removed is arranged on the second special-shaped curved surface, the first special-shaped curved surface is the opposite surface of the surface of the laser additive manufacturing thin-walled special-shaped curved surface part to be removed. Adding supports on both sides of the part will hinder the support removal auxiliary device from working, so the supports are added on one side of the part. In some embodiments of the present application, the laser additive manufacturing thin-walled special-shaped curved surface part to which the removal method is applied includes opposite first and second special-shaped curved surfaces, wherein the first special-shaped curved surface is the surface on one side of the center of curvature of the laser additive manufacturing thin-walled special-shaped curved surface part, also known as the inner curved surface; the second special-shaped curved surface is the surface on the side away from the center of curvature of the laser additive manufacturing thin-walled special-shaped curved surface part, also known as the outer curved surface; and the support to be removed is arranged on the first special-shaped curved surface.

[0026] The present application also provides a laser additive manufacturing method for thin-walled special-shaped curved surface parts, characterized by comprising the following steps:

[0027] a) establishing a CAD digital model of the laser additive manufacturing thin-walled special-shaped curved surface part;

[0028] b) according to the CAD digital model obtained in step a), using laser additive manufacturing to manufacture the part, to obtain a laser additive manufacturing thin-walled special-shaped curved surface part;

[0029] c) using any of the above-described removal methods to remove the supports of the laser additive manufacturing thin-walled special-shaped curved surface part obtained in step b), to obtain a thin-walled special-shaped curved surface part.

[0030] The present application first establishes a CAD digital model of a laser additive manufacturing thin-walled special-shaped curved surface part. The laser additive manufacturing thin-walled special-shaped curved surface part described in the present application is the same as the laser additive manufacturing thin-walled special-shaped curved surface part targeted by the above-described removal method, and will not be repeated. Specifically, in this process, a suitable part placement angle is selected, and the supports are all added to the first special-shaped curved surface or the second special-shaped curved surface of the part. The support removal auxiliary device will be subsequently arranged on the opposite surface of the surface where the support is located, i.e., the outer surface on the other side of the part where the support is located. Adding supports on both sides of the part will hinder the support removal auxiliary device from functioning, so the supports are all added to one side of the part.

[0031] After the present application establishes a CAD digital model of a laser additive manufacturing thin-walled special-shaped curved surface part, according to the CAD digital model obtained in step a), using laser additive manufacturing to manufacture the part, to obtain a laser additive manufacturing thin-walled special-shaped curved surface part. Specifically, the metal powder is placed in the powder bin of the laser additive manufacturing equipment, and according to the established CAD digital model, the part manufacturing with supports is completed through laser additive manufacturing technology, to obtain a laser additive manufacturing thin-walled special-shaped curved surface part.

[0032] After the present application obtains a laser additive manufacturing thin-walled special-shaped curved surface part, using any of the above-described removal methods to remove the supports of the laser additive manufacturing thin-walled special-shaped curved surface part obtained in step b), to obtain a thin-walled special-shaped curved surface part. After the present application removes the supports of the laser additive manufacturing thin-walled special-shaped curved surface part obtained in step b), it further includes sandblasting treatment of the part after support removal, to obtain a thin-walled special-shaped curved surface part.

[0033] The present application also provides a support removal auxiliary device for laser additive manufacturing thin-walled special-shaped curved surface parts, which is the same as the above-described support removal auxiliary device and will not be repeated.

[0034] The application discloses a support removal method for laser additive manufacturing of thin-wall special-shaped curved surface parts and application and a support removal auxiliary device.The support removal method is characterized in that a support removal auxiliary device is formed by a conformal main body structure 1 and a water cooling device 2, and the part is simultaneously air-cooled and liquid-cooled during the support removal process, so that the temperature of the part is reduced, the thermal stress is reduced, the large size deformation of the part is inhibited, and the forming quality is improved. BRIEF DESCRIPTION OF DRAWINGS

[0035] Figure 1 It is a front view of the support removal auxiliary device in the embodiment 1 of the application;

[0036] Figure 2 It is a side view of the support removal auxiliary device in the embodiment 1 of the application;

[0037] Figure 3 It is a top view of the support removal auxiliary device in the embodiment 1 of the application;

[0038] Figure 4 It is a sectional view of A-A in the embodiment 1 of the application; Figure 1

[0039] It is a sectional view of B-B in the embodiment 1 of the application; Figure 5 Figure 1 It is an enlarged view of the region B in the embodiment 1 of the application;

[0040] Figure 6 Figure 5 It is a sectional view of BC-BC in the embodiment 1 of the application;

[0041] Figure 7 It is a sectional view of BD-BD in the embodiment 1 of the application; Figure 5

[0042] Figure 8 Figure 5

[0043] Figure 9 It is a front view of the water cooling device in the embodiment 1 of the application;

[0044] Figure 10 It is a side view of the water cooling device in the embodiment 1 of the application;

[0045] Figure 11 It is a top view of the water cooling device in the embodiment 1 of the application;

[0046] ​​​​Figure 12 This is a schematic diagram of the part support removal process in Embodiment 1 of the present invention;

[0047] Wherein: 1 is the main structure, 2 is the water cooling device, 3 is the part, 4 is the support to be removed, 5 is the workbench, 101 is the water cooling device fixing mechanism, 102 is the cavity, 103 is the air inlet, 104 is the air outlet, 111 is the water cooling device interface, 201 is the cooling water channel, and 202 is the connecting column. Detailed Implementation

[0048] This invention discloses a method for removing supports in laser additive manufacturing of thin-walled irregular curved surface parts, its application, and an auxiliary device for support removal. Those skilled in the art can refer to the content of this document and appropriately modify the process parameters to achieve the desired result. It should be particularly noted that all similar substitutions and modifications are obvious to those skilled in the art and are considered to be included in this invention. The method and application of this invention have been described through preferred embodiments, and those skilled in the art can clearly modify or appropriately change and combine the method and application described herein without departing from the content, spirit, and scope of this invention to realize and apply the technology of this invention.

[0049] This invention provides a method for laser selective melting additive manufacturing and support removal of a GH5188 high-temperature alloy support plate for aero-engines. For example... Figures 1-12 As shown, Figure 1 This is a front view of the support removal auxiliary device in Embodiment 1 of the present invention; Figure 2 This is a side view of the support removal auxiliary device in Embodiment 1 of the present invention; Figure 3 This is a top view of the support removal auxiliary device in Embodiment 1 of the present invention; Figure 4 for Figure 1 A cross-sectional view of the AA plane; Figure 5 for Figure 1 A magnified view of a portion of region B in the middle; Figure 6 for Figure 5 A sectional view of the BC-BC plane; Figure 7 for Figure 5 Sectional view of the BD-BD plane; Figure 8 for Figure 5 A cross-sectional view of the BE-BE plane; Figure 9 This is a front view of the water-cooling device in Embodiment 1 of the present invention; Figure 10 This is a side view of the water-cooling device in Embodiment 1 of the present invention; Figure 11 This is a top view of the water-cooling device in Embodiment 1 of the present invention; Figure 12 This is a schematic diagram of the part support removal process in Embodiment 1 of the present invention.

[0050] The present invention will be further described below with reference to the embodiments:

[0051] Example 1

[0052] The embodiment gives a laser selective melting additive manufacturing and support removal method of an aero-engine GH5188 high-temperature alloy support plate, and the support plate has a wall thickness of 5 mm, which is a typical thin-walled special-shaped curved surface part.

[0053] The specific steps of the laser selective melting additive manufacturing and support removal of the aero-engine GH5188 high-temperature alloy support plate are as follows:

[0054] Step one: establishing a CAD digital model of the GH5188 high-temperature alloy support plate.

[0055] Step two: taking the GH5188 high-temperature alloy powder with a particle size of 15 μm to 53 μm as a raw material, and completing the manufacturing of the support plate with support according to the CAD digital model established in step one through the laser selective melting additive manufacturing technology. The process parameters used are: laser power 280 W, laser scanning speed 980 mm / s, and layer thickness 60 μm.

[0056] Step three: establishing a CAD model of the main body structure 1 of the support removal auxiliary device. The main body structure 1 of the support removal auxiliary device has a wall thickness of 10 mm, the diameters of the two air inlet holes 103 are both 15 mm, the inner diameter of the water cooling device interface 111 is 20 mm, and the wall thickness of the water cooling device interface 111 is 5 mm. The center distance between the adjacent two air outlet holes 104 is 10 mm, and the center distance between the adjacent two groups of air outlet holes 104 is 40 mm. The large flat-top cone of the air outlet hole 104 has a bottom diameter of 4 mm, a top diameter of 2.5 mm, and a height of 4 mm. The small flat-top cone of the air outlet hole 104 has a bottom diameter of 2.5 mm, a top diameter of 2 mm, and a height of 6 mm. The center symmetry axes of all the large flat-top cones of the air outlet holes 104 are parallel to the normal directions of the surfaces. The center symmetry axis of the small flat-top cone of the array center air outlet hole 104 is parallel to the center symmetry axis of the large flat-top cone. The included angle between the center symmetry axes of the small flat-top cones of the four air outlet holes 104 at the four corners and the center symmetry axes of the large flat-top cones is 60°. The included angle between the center symmetry axes of the small flat-top cones of the four air outlet holes 104 at the four edges and the center symmetry axes of the large flat-top cones is 50°.

[0057] Step four: taking the Al2O3 ceramic powder with an average particle size D 50 of 0.3 μm as a raw material, and completing the manufacturing of the main body structure 1 of the ceramic support removal auxiliary device according to the CAD digital model established in step three through the selective laser sintering technology. The process parameters used are: laser power 21 W, laser scanning speed 1600 mm / s, and layer thickness 150 μm.

[0058] Step five: Establish CAD model of water cooling device 2. The wall thickness of water cooling device 2 is 5 mm, and the diameter of cooling water channel 201 is 10 mm.

[0059] Step six: Use copper alloy powder with particle size between 15 μm and 53 μm as raw material, and complete the manufacturing of copper alloy water cooling device 2 by laser selective melting additive manufacturing technology according to the CAD digital model established in step five. The process parameters used are: laser power 340 W, laser scanning speed 400 mm / s, layer thickness 50 μm.

[0060] Step seven: Water cooling device 2 is installed on main body structure 1 by inserting water cooling device interface 111 on water cooling device fixing mechanism 101.

[0061] Step eight: Fix the support plate on the workbench, place the support removal auxiliary device outside the support plate, and make the water cooling device 2 close to the surface of the support plate.

[0062] Step nine: Use tools such as pliers and files to mechanically remove the support to be removed, and perform air cooling and water cooling on the support plate during the removal process.

[0063] Step ten: Sandblasting treatment is performed on the support plate after the support is removed, and the manufacturing of the support plate is completed.

[0064] Example 2

[0065] This example gives a laser selective melting additive manufacturing and support removal method for K477 high-temperature alloy blade. The blade is 2 mm thick, which is a typical thin-walled special-shaped curved surface part. The specific steps are as follows:

[0066] Step one: Establish CAD digital model of K477 high-temperature alloy blade.

[0067] Step two: Use K477 high-temperature alloy powder with particle size between 15 μm and 53 μm as raw material, and complete the manufacturing of the blade with support by laser selective melting additive manufacturing technology according to the CAD digital model established in step one. The process parameters used are: laser power 280 W, laser scanning speed 980 mm / s, layer thickness 60 μm.

[0068] Step three: Establish CAD model of the main body structure 1 of the support removal auxiliary device. The wall thickness of the main body structure 1 of the support removal auxiliary device is 7 mm, the diameter of the two air inlet holes 103 is 12 mm, the inner diameter of the water cooling device interface 111 is 14 mm, and the wall thickness of the water cooling device interface 111 is 4 mm. The center distance between the adjacent two air outlet holes 104 is 6 mm, and the center distance between the adjacent two groups of air outlet holes 104 is 24 mm. The bottom diameter of the large flat top cone of the air outlet hole 104 is 3.8 mm, the top diameter is 2 mm, and the height is 3 mm. The bottom diameter of the small flat top cone of the air outlet hole 104 is 2 mm, the top diameter is 1.5 mm, and the height is 4 mm. The center symmetry axis of the large flat top cone of all air outlet holes 104 is parallel to the normal direction of the surface. The center symmetry axis of the small flat top cone of the array center air outlet hole 104 is parallel to the center symmetry axis of the large flat top cone. The angle between the center symmetry axis of the small flat top cone of the four air outlet holes 104 at the four corners and the center symmetry axis of the large flat top cone is 45°. The angle between the center symmetry axis of the small flat top cone of the four air outlet holes 104 at the four edges and the center symmetry axis of the large flat top cone is 35°.

[0069] Step four: Al2O3 ceramic powder with an average particle size D 50 of 0.3 μm is used as the raw material, and the CAD digital model established in step three is used to complete the manufacturing of the main body structure 1 of the ceramic support removal auxiliary device by selective laser sintering technology. The process parameters used are: laser power 21 W, laser scanning speed 1600 mm / s, and layer thickness 150 μm.

[0070] Step five: Establish CAD model of water cooling device 2. The wall thickness of the water cooling device 2 is 3.5 mm, and the diameter of the cooling water channel 201 is 7 mm.

[0071] Step six: Copper alloy powder with a particle size of 15 μm to 53 μm is used as the raw material, and the CAD digital model established in step five is used to complete the manufacturing of the copper alloy water cooling device 2 by laser selective melting additive manufacturing technology. The process parameters used are: laser power 340 W, laser scanning speed 400 mm / s, and layer thickness 50 μm.

[0072] Step seven: The water cooling device 2 is installed on the main body structure 1 by inserting the water cooling device interface 111 on the water cooling device fixing mechanism 101.

[0073] Step eight: Fix the blade on the workbench, place the support removal auxiliary device outside the blade, and make the water cooling device 2 tightly adhere to the surface of the blade.

[0074] Step nine: mechanical removal of the blade using pliers, files and other tools, and air and water cooling during the removal process.

[0075] Step ten: sandblasting of the platform after removal of the blade, completing the manufacture of the blade.

[0076] Example 3

[0077] This example gives a laser selective melting additive manufacturing and support removal method for a TC4 titanium alloy blade, which has a wall thickness of 1 mm and is a typical thin-walled special-shaped curved surface part. The specific steps are as follows:

[0078] Step one: establish a CAD digital model of the TC4 titanium alloy blade.

[0079] Step two: using TC4 titanium alloy powder with a particle size of 15-53 μm as the raw material, and according to the CAD digital model established in step one, the blade with support is manufactured by laser selective melting additive manufacturing technology. The process parameters used are: laser power 280 W, laser scanning speed 1250 mm / s, layer thickness 60 μm.

[0080] Step three: establish a CAD model of the main structure 1 of the support removal auxiliary device. The main structure 1 of the support removal auxiliary device has a wall thickness of 5 mm, the two air inlet holes 103 each have a diameter of 10 mm, the water cooling device interface 111 has an inner diameter of 11 mm and a wall thickness of 3 mm. The center distance between adjacent two air outlet holes 104 is 5 mm, and the center distance between adjacent two groups of air outlet holes 104 is 20 mm. The large flat-top cone of the air outlet hole 104 has a bottom diameter of 3 mm, a top diameter of 1.5 mm and a height of 2 mm. The small flat-top cone of the air outlet hole 104 has a bottom diameter of 1.5 mm, a top diameter of 1 mm and a height of 3 mm. The center symmetry axes of all large flat-top cones of the air outlet holes 104 are parallel to the normal direction of the surface. The center symmetry axis of the small flat-top cone of the array center air outlet hole 104 is parallel to the center symmetry axis of the large flat-top cone. The center symmetry axes of the small flat-top cones of the four air outlet holes 104 at the four corners of the array make an angle of 40° with the center symmetry axes of the large flat-top cones. The center symmetry axes of the small flat-top cones of the four air outlet holes 104 at the four edges of the array make an angle of 30° with the center symmetry axes of the large flat-top cones.

[0081] Step four: using TC4 titanium alloy powder with an average particle size D 50The Al2O3 ceramic powder with a particle size of 0.3 μm is used as the raw material, and the main structure 1 of the ceramic support removal auxiliary device is manufactured by selective laser sintering technology according to the CAD digital model established in step three. The process parameters used are: laser power 21 W, laser scanning speed 1600 mm / s, and layer thickness 150 μm.

[0082] Step five: Establish the CAD model of the water cooling device 2. The wall thickness of the water cooling device 2 is 3 mm, and the diameter of the cooling water channel 201 is 5 mm.

[0083] Step six: The copper alloy powder with a particle size of 15 μm to 53 μm is used as the raw material, and the copper alloy water cooling device 2 is manufactured by laser selective melting additive manufacturing technology according to the CAD digital model established in step five. The process parameters used are: laser power 340 W, laser scanning speed 400 mm / s, and layer thickness 50 μm.

[0084] Step seven: The water cooling device 2 is installed on the main structure 1 by inserting the water cooling device interface 111 on the water cooling device fixing mechanism 101.

[0085] Step eight: The blade is fixed on the workbench, the support removal auxiliary device is placed outside the blade, and the water cooling device is tightly attached to the surface of the blade.

[0086] Step nine: The blade is mechanically removed using pliers, files and other tools, and the blade is air-cooled and water-cooled during the removal process.

[0087] Step ten: The blade is manufactured by sandblasting the support plate after the blade is removed.

[0088] The above is only a preferred specific embodiment of the present application, but the protection scope of the present application is not limited thereto, and any person skilled in the art can make equivalent replacements or changes to the technical solution and the inventive concept of the present application within the technical range disclosed by the present application, which should be covered within the protection scope of the present application.

Claims

1. A method for removing supports in laser additive manufacturing of thin-walled irregular curved surface parts, characterized in that, Includes the following steps: S1) Provides a support removal auxiliary device, which includes a main structure (1) and a water cooling device (2); The main structure (1) includes a first surface and a second surface. The main structure (1) is provided with a cooling gas channel connecting the first surface and the second surface. The first surface matches the opposite surface of the surface where the support to be removed of the thin-walled irregular curved surface part of the laser additive manufacturing is located, so that the gas discharged from the cooling gas channel can cover the opposite surface of the surface where the support to be removed of the thin-walled irregular curved surface part of the laser additive manufacturing is located. The end face of the main structure (1) is provided with a water cooling device fixing mechanism (101), and the water cooling device fixing mechanism (101) is provided with a water cooling device interface (111). The water cooling device (2) is provided with a cooling water channel (201) inside; the water cooling device (2) is provided with a connecting post (202) that cooperates with the water cooling device interface (111) so that the water cooling device (2) can be fixed to the end face of the main structure (1) by the water cooling device fixing mechanism (101) and the surface of the water cooling device (2) can be in contact with the opposite surface of the surface to be removed of the support of the laser additive manufacturing thin-walled irregular curved surface part; S2) The surface of the water cooling device (2) of the support removal auxiliary device described in step S1) is attached to the opposite surface of the support to be removed of the thin-walled irregular curved surface part of the laser additive manufacturing, while cooling gas is introduced into the cooling gas channel and coolant is introduced into the cooling water channel (201), and the support to be removed of the thin-walled irregular curved surface part of the laser additive manufacturing is mechanically removed. The laser additive manufacturing thin-walled irregular curved surface part includes a first irregular curved surface and a second irregular curved surface, and all the supports to be removed are disposed on the first irregular curved surface; the first irregular curved surface is the surface on the side where the curvature center of the laser additive manufacturing thin-walled irregular curved surface part is located, and the second irregular curved surface is the surface on the side away from the curvature center of the laser additive manufacturing thin-walled irregular curved surface part.

2. The removal method according to claim 1, characterized in that, In step S1), the main structure (1) has a cavity (102) with a wall thickness of 5 mm to 10 mm inside. The first surface is provided with a through air outlet (104), and the second surface is provided with a through air inlet (103). The air outlet (104) and the air inlet (103) are connected to the cavity (102) to form a cooling gas channel. The first surface has multiple sets of air outlet arrays, each set of air outlet arrays consists of 3×3 air outlets (104) in the longitudinal and transverse directions, the center-to-center distance between two adjacent air outlets (104) is 5 mm to 10 mm, and the center-to-center distance between the air outlets (104) at the center of two adjacent sets of air outlet arrays is 20 mm to 40 mm. The second surface has two air inlets (103) arranged longitudinally, the diameter of which is 10 mm to 15 mm; The water cooling device interface (111) is a through hole with an inner diameter of 11 mm to 20 mm, and the wall thickness of the water cooling device interface (111) is 3 mm to 5 mm.

3. The removal method according to claim 2, characterized in that, The vent (104) is formed by coaxially connecting a first flat-topped truncated cone section and a second flat-topped truncated cone section; the large end of the first flat-topped truncated cone section is connected to the cavity (102), and the small end coincides with the large end of the second flat-topped truncated cone section at the mating surface; the small end of the second flat-topped truncated cone section faces the first surface. The diameter of the large end face of the first flat-topped truncated cone hole section is 3 mm to 4 mm, the diameter of the small end face of the first flat-topped truncated cone hole section is 1.5 mm to 2.5 mm, and the length of the first flat-topped truncated cone hole section is 2 mm to 4 mm. The diameter of the large end face of the second flat-topped truncated cone hole section is 1.5 mm to 2.5 mm, the diameter of the small end face of the second flat-topped truncated cone hole section is 1 mm to 2 mm, and the length of the second flat-topped truncated cone hole section is 3 mm to 6 mm.

4. The removal method according to claim 3, characterized in that, In the array of air outlets, the central axis of symmetry of the first flat-topped truncated cone hole segment of all air outlets (104) is parallel to the normal direction of the surface where the large end is located. In the air outlet array, the angle between the central axis of symmetry of the second flat-topped truncated cone segment of one of the air outlets (104) at the center of the array and the central axis of symmetry of the first flat-topped truncated cone segment is 0°. In the air outlet array, the angle between the central axis of symmetry of the second flat-topped truncated cone hole segment and the central axis of symmetry of the first flat-topped truncated cone hole segment of each of the four air outlets (104) at the four corners of the array is 40°~60°. In the air outlet array, the angle between the central axis of symmetry of the second flat-topped truncated cone hole segment and the central axis of symmetry of the first flat-topped truncated cone hole segment of each of the four air outlets (104) on the four sides of the array is 30°~50°.

5. A laser additive manufacturing method for thin-walled irregular curved surface parts, characterized in that, Includes the following steps: a) Establish a CAD digital model for laser additive manufacturing of thin-walled irregular curved surface parts; b) Based on the CAD digital model obtained in step a), laser additive manufacturing is used to produce thin-walled irregular curved surface parts; c) The thin-walled irregular curved surface part obtained in step b) is subjected to support removal using any of the removal methods described in claims 1 to 4 to obtain the thin-walled irregular curved surface part.

6. A support removal auxiliary device for laser additive manufacturing of thin-walled irregular curved surface parts, characterized in that, It includes the main structure (1) and a water cooling device (2); The main structure (1) includes a first surface and a second surface. The main structure (1) is provided with a cooling gas channel connecting the first surface and the second surface. The first surface is opposite to the surface where the support to be removed of the laser additive manufacturing thin-walled irregular curved surface part is located, so that the gas discharged from the cooling gas channel can fit against the opposite surface where the support to be removed of the laser additive manufacturing thin-walled irregular curved surface part is located. The end face of the main structure (1) is provided with a water cooling device fixing mechanism (101), and the water cooling device fixing mechanism (101) is provided with a water cooling device interface (111). The water cooling device (2) is provided with a cooling water channel (201) inside; the water cooling device (2) is provided with a connecting post (202) that cooperates with the water cooling device interface (111) so that the water cooling device (2) can be fixed to the end face of the main structure (1) by the water cooling device fixing mechanism (101) and the surface of the water cooling device (2) can be in contact with the opposite surface of the surface to be removed of the support of the laser additive manufacturing thin-walled irregular curved surface part; The laser additive manufacturing thin-walled irregular curved surface part includes a first irregular curved surface and a second irregular curved surface, and all the supports to be removed are disposed on the first irregular curved surface; the first irregular curved surface is the surface on the side where the curvature center of the laser additive manufacturing thin-walled irregular curved surface part is located, and the second irregular curved surface is the surface on the side away from the curvature center of the laser additive manufacturing thin-walled irregular curved surface part.

7. The support removal auxiliary device according to claim 6, characterized in that, The main structure (1) has a cavity (102) with a wall thickness of 5 mm to 10 mm inside. The first surface is provided with a through air outlet (104), and the second surface is provided with a through air inlet (103). The air outlet (104) and the air inlet (103) are connected to the cavity (102) to form a cooling gas channel. The first surface has multiple sets of air outlet arrays, each set of air outlet arrays consists of 3×3 air outlets (104) in the longitudinal and transverse directions, the center-to-center distance between two adjacent air outlets (104) is 5 mm to 10 mm, and the center-to-center distance between the air outlets (104) at the center of two adjacent sets of air outlet arrays is 20 mm to 40 mm. The second surface has two air inlets (103) arranged longitudinally, the diameter of which is 10 mm to 15 mm; The water cooling device interface (111) is a through hole with an inner diameter of 11 mm to 20 mm, and the wall thickness of the water cooling device interface (111) is 3 mm to 5 mm.

8. The support removal auxiliary device according to claim 7, characterized in that, The vent (104) is formed by coaxially connecting a first flat-topped truncated cone section and a second flat-topped truncated cone section; the large end of the first flat-topped truncated cone section is connected to the cavity (102), and the small end coincides with the large end of the second flat-topped truncated cone section at the mating surface; the small end of the second flat-topped truncated cone section faces the first surface. The diameter of the large end face of the first flat-topped truncated cone hole section is 3 mm to 4 mm, the diameter of the small end face of the first flat-topped truncated cone hole section is 1.5 mm to 2.5 mm, and the length of the first flat-topped truncated cone hole section is 2 mm to 4 mm. The diameter of the large end face of the second flat-topped truncated cone hole section is 1.5 mm to 2.5 mm, the diameter of the small end face of the second flat-topped truncated cone hole section is 1 mm to 2 mm, and the length of the second flat-topped truncated cone hole section is 3 mm to 6 mm.

9. The support removal auxiliary device according to claim 8, characterized in that, In the array of air outlets, the central axis of symmetry of the first flat-topped truncated cone hole segment of all air outlets (104) is parallel to the normal direction of the surface where the large end is located. In the air outlet array, the angle between the central axis of symmetry of the second flat-topped truncated cone segment of one of the air outlets (104) at the center of the array and the central axis of symmetry of the first flat-topped truncated cone segment is 0°. In the air outlet array, the angle between the central axis of symmetry of the second flat-topped truncated cone hole segment and the central axis of symmetry of the first flat-topped truncated cone hole segment of each of the four air outlets (104) at the four corners of the array is 40°~60°. In the air outlet array, the angle between the central axis of symmetry of the second flat-topped truncated cone hole segment and the central axis of symmetry of the first flat-topped truncated cone hole segment of each of the four air outlets (104) on the four sides of the array is 30°~50°.

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