Casting lamination preparation method of integrated ceramic mechanical arm

Abstract

The invention belongs to the technical field of mechanical arms, and particularly discloses a casting lamination preparation method of an integrated ceramic mechanical arm. The method comprises the following steps: firstly, preparing an evanescent mold, and preparing a hollow gas groove ceramic casting sheet with the same shape as the evanescent mold according to the shape of the evanescent mold; then putting the lost foam into a hollow part of a gas groove ceramic cast sheet, arranging laminated ceramic cast sheets on two sides, and punching to obtain a green body; and then the green body is sequentially subjected to warm isostatic pressing treatment, rubber discharging treatment, degreasing treatment and sintering treatment, and the integrated ceramic mechanical arm is obtained. According to the casting lamination preparation method of the ceramic mechanical arm, the problems that an existing integrated sintering ceramic mechanical arm is poor in air tightness and a traditional mechanical arm is complex in preparation process and high in glue requirement are solved.

Description

Technical Field

[0001] The present invention relates to the technical field of mechanical arms, and in particular to a tape-casting lamination preparation method for an integrated ceramic mechanical arm. Background Art

[0002] The robotic arms used in the semiconductor processing industry usually have ventilation slots and air holes. When in use, the wafer can be moved after vacuuming the wafer by pumping air from the air holes. This method of transportation can achieve light contact, so it is not easy to damage the workpiece. In addition, to adapt to the special environment of wafer processing, the robotic arms also have the properties of not polluting the wafer, high temperature resistance, and acid and alkali corrosion resistance.

[0003] Ceramic robotic arms play a role in handling in semiconductor equipment, responsible for carrying silicon wafers to designated locations. Because silicon wafers are extremely susceptible to contamination by other particles, they are generally carried out in a vacuum environment, and strict requirements are placed on the material and performance of the robotic arms. In this environment, robotic arms made of most materials generally have difficulty completing their work, and the materials used to make robotic arms need to be resistant to high temperatures, wear-resistant, high in hardness, and high in purity. Therefore, ceramic materials have become the preferred material for robotic arms.

[0004] For the production of ceramic robotic arms, the more mature technology currently generally adopts the splicing method. Specifically, two ceramic sheets are processed separately according to the drawings, and then bonded with a specific glue. Finally, the outer contour is processed and the bonding surface is flat-ground to obtain a ceramic robotic arm. However, since ceramics are more brittle and harder than metals, the processing difficulty is greater than that of metals, the processing cost is higher, and defects are generated during processing and are extremely difficult to repair. Therefore, the ceramic robotic arm obtained by the above method has the following limitations: First, the processing is complicated, and two ceramic sheets need to be processed, the processing time is long, and the cost is high; second, the performance requirements of the glue are high, especially the glue is required to be resistant to high temperatures, and the requirements for the gluing technology are high, such as ensuring the airtightness of the ceramic robotic arm, the air groove is not blocked, and the product after gluing needs to be processed to the flatness accuracy required; in addition, the thickness of the glue is strictly controlled, and the glue composition to be selected is appropriate to ensure that it does not contaminate the wafer during use.

[0005] With the advancement of technology, there is currently a plan to apply integrated sintering technology to the manufacture of ceramic robotic arms. For example, a ceramic robotic arm includes a top structure, an intermediate plate structure, and a bottom structure that are stacked in sequence; the top structure, the intermediate plate structure, and the bottom structure have the same external dimensions and are connected as one; the method for preparing a ceramic robotic arm using integrated sintering technology specifically includes the following steps: 1. Casting ceramic raw tape; 2. Punching the external shape and assembly holes on all ceramic raw tapes, and then punching grooves and suction holes for suction cups on different ceramic raw tapes; 3. Stacking and hot pressing the punched ceramic raw tapes; 4. Sintering the hot-stacked ceramic raw tapes into an integrated form; 5. Trimming and subsequent processing of the vacuum arm formed after sintering.

[0006] And the Chinese patent application (CN 117901168A) also proposed an improvement plan, including the selection of cast sheet material, purity and thickness, cast sheet laser cutting and impurity removal, cast sheet vacuum drying, cast sheet combination stacking and ceramic robot arm finishing. When the airtightness test process finds that the airtightness of the product does not meet the preset requirements, the ceramic robot arm is self-healed and repaired. However, although the above two schemes have reduced the machining links, the airtightness cannot be guaranteed by one sintering, especially for the latter, the scheme will also introduce new corrosion-resistant components (the self-healing component used in the scheme is SiO2, which is not corrosion-resistant, which will limit the application of the scheme in ceramic robot arms). Therefore, the preparation scheme of ceramic robot arms needs to be improved urgently. Summary of the invention

[0007] In view of this, the present invention provides a method for preparing an integrated ceramic robotic arm through cast lamination, which can solve the problems of poor air tightness and corrosion resistance of the ceramic robotic arm, simplify the traditional split preparation process of the robotic arm, save processing costs, and remove glue at the same time, solving the problems of the glue itself being not resistant to high temperatures, not being environmentally friendly, and having poor air tightness when there is less glue.

[0008] In order to achieve the above object, the present invention adopts the following technical solution:

[0009] The method for preparing a tape-cast laminate of an integrated ceramic robot arm comprises the following steps:

[0010] 1) preparing an evaporative mold, and preparing a ceramic cast sheet with an air groove having the same shape as the evaporative mold according to the shape of the evaporative mold;

[0011] 2) placing the lost mold in the hollow of the air slot ceramic cast sheet, arranging the overlapping ceramic cast sheets on both sides, and obtaining the green body after punching;

[0012] 3) The green body obtained in step 2) is subjected to warm isostatic pressing, binder removal, and degreasing and sintering in sequence to obtain an integrated ceramic robotic arm.

[0013] Preferably, the lost mold comprises one of graphite paper and carbon-based sacrificial slurry.

[0014] Preferably, the preparation method of the carbon-based sacrificial slurry is: mix and ball-mill the carbon material, a high-boiling point solvent, a low-boiling point solvent and a dispersing binder to obtain a preliminary mixture; mix and ball-mill the preliminary mixture with a diluent solvent to obtain a pre-slurry; mix and stir the pre-slurry with a slurry modifier to obtain a carbon-based sacrificial slurry.

[0015] Preferably, the carbon material includes one or more of carbon black, graphite powder and graphene;

[0016] The high boiling point solvent includes terpineol and / or ethylene glycol butyl ether;

[0017] The low boiling point solvent includes methanol and / or ethanol;

[0018] The dispersed binder includes one or more of vinyl, cellulose and acrylic resins;

[0019] The dilution solvent includes one or more of butyl acetate, methyl acetate, ethyl acetate and n-propyl acetate;

[0020] The slurry modifier includes one or more of a defoamer, a thixotropic agent and a leveling agent.

[0021] Preferably, the volume of the expendable mold = the hollowing out of the air groove ceramic cast sheet × the shrinkage rate of the air groove ceramic cast sheet.

[0022] Preferably, the position of the punching hole in step 2) is located within the orthographic projection of the lost mold on the laminated ceramic cast sheet.

[0023] Preferably, the temperature of the warm isostatic pressing treatment is 50-80° C., the pressure is 8-18 MPa, and the time is 5-60 min.

[0024] Preferably, the debinding step is to place the green body after warm isostatic pressing horizontally, and heat it at 50 to 300° C. for 1 to 8 hours to complete the debinding treatment.

[0025] Preferably, the temperature of the degreasing treatment is 200-450° C., and the time of the degreasing sintering treatment is 2-4 hours.

[0026] Preferably, the sintering temperature is 1500-1700° C., and the sintering time is 1-4 hours.

[0027] It can be seen from the above technical solutions that compared with the prior art, the present invention has the following beneficial effects: In the tape-cast lamination preparation method of the integrated ceramic robot arm of the preferred embodiment of the present invention, the split processing and gluing process of the split processing and gluing ceramic robot arm is omitted, saving processing costs, while avoiding the problems of blocking the exhaust groove due to excessive glue, and air leakage due to insufficient glue, which affect the adsorption force, and also solves the problem that the resin glue itself is not resistant to high temperature and the glue is easy to pollute the environment. At the same time, the high-temperature bonding oxide between the new integrated arm ceramic sheets is omitted, and the crystals formed by the high temperature of the material of the ceramic body itself are connected and sealed, which has high sealing and corrosion resistance. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the provided drawings without paying creative work.

[0029] Figure 1 This is a physical picture of the integrated ceramic mechanical arm obtained in Example 1 of the present invention;

[0030] Figure 2 This is a side fracture view of the robotic arm obtained in Example 1 of the present invention;

[0031] Figure 3 This is a diagram of the mechanical arm interface obtained in Comparative Example 1 of the present invention;

[0032] Figure 4 This is a physical picture of the robotic arm obtained in comparative example 2 of the present invention. DETAILED DESCRIPTION

[0033] The present invention provides a method for preparing a tape-cast laminate of an integrated ceramic robot arm, comprising the following steps:

[0034] 1) preparing an evaporative mold, and preparing a ceramic cast sheet with an air groove having the same shape as the evaporative mold according to the shape of the evaporative mold;

[0035] 2) placing the lost mold in the hollow of the air slot ceramic cast sheet, arranging the overlapping ceramic cast sheets on both sides, and obtaining the green body after punching;

[0036] 3) The green body obtained in step 2) is subjected to warm isostatic pressing, binder removal, degreasing and sintering in sequence to obtain an integrated ceramic robotic arm.

[0037] In the present invention, the lost mold comprises one of graphite paper and carbon-based sacrificial slurry.

[0038] In the present invention, the preparation method of the carbon-based sacrificial slurry is: mix and ball-mill the carbon material, a high boiling point solvent, a low boiling point solvent and a dispersing binder to obtain a preliminary mixture; mix and ball-mill the preliminary mixture with a diluent solvent to obtain a pre-slurry; mix and stir the pre-slurry with a slurry modifier to obtain a carbon-based sacrificial slurry.

[0039] In the present invention, the carbon material includes one or more of carbon black, graphite powder and graphene;

[0040] The high boiling point solvent includes terpineol and / or ethylene glycol butyl ether;

[0041] The low boiling point solvent includes methanol and / or ethanol

[0042] The dispersed binder includes one or more of vinyl, cellulose and acrylic resins;

[0043] The dilution solvent includes one or more of butyl acetate, methyl acetate, ethyl acetate and n-propyl acetate;

[0044] The slurry modifier includes one or more of a defoamer, a thixotropic agent and a leveling agent.

[0045] The slurry modifier improves fluidity and softness, and can be one or more of dibutyl oxalate, ethylene glycol, propylene glycol, and tricresyl phosphate.

[0046] In the present invention, the lost mold can also be a binary lost mold composed of paraffin wax, acrylic, etc. and carbon-based materials such as plastic mesh, paper, and cloth. Although a single paraffin wax can usually be easily formed at 100°C and has a certain rigidity after curing, it softens quickly and cannot guarantee continuous support until the cast film has sufficient rigidity. By compounding paraffin wax and acrylic that are easy to soften at low temperatures with carbon-based materials such as plastic mesh, paper, and cloth with higher ablation temperatures, the rigidity can be maintained to 300°C and gradually eliminated, and no impurities remain after sintering. The reference process is: place a metal plate on the heating table, cut the dust-free cloth into thin strips with a width of 5mm and place it on the iron plate, surround the dust-free cloth strips with four iron sheets with a thickness of 0.5mm, spread refined paraffin powder, place a metal block larger than the cloth strip on the iron plate, turn on the heating table and heat to 60-80°C, heat for 10-60min, so that the paraffin softens but does not melt. The iron sheet is compacted with a heated metal block, and after cooling, an evaporative mold with a certain rigidity is obtained.

[0047] In this field, it is difficult to obtain a lost mold with regular morphology and controllable size at low cost. Plastic and other carbon-based materials are used as lost molds. Although it is easy to form, it is difficult to discharge. At the same time, the material itself is too flexible and is easy to bend during the blank pressing and forming, causing the finished product venting groove to deform. Using paraffin as a lost mold is easy to discharge, but it is difficult to obtain the desired regular and controllable shape. The lost mold disclosed in the present invention is made of a material with sufficient rigidity, and is easy to form, hard, and easy to discharge.

[0048] In the present invention, the volume of the expendable mold = the hollowing out of the air slot ceramic cast sheet × the shrinkage rate of the air slot ceramic cast sheet.

[0049] The shrinkage rate of the air slot ceramic cast sheet = (original size - size after shrinkage) / original size × 100%.

[0050] In the present invention, the position of the punching hole in step 2) is located within the orthographic projection of the evaporative die on the laminated ceramic cast sheet.

[0051] In the present invention, a stacking step is also included before punching, and the stacking temperature is 50-80°C, specifically 55°C, 60°C, 65°C, 70°C, and 75°C; the stacking pressure is 10-20MPa, specifically 12MPa, 14MPa, 15MPa, 16MPa, and 18MPa; the stacking time is 8-15min, specifically 9min, 10min, 12min, and 14min.

[0052] In the present invention, the air groove ceramic cast sheet and the laminated ceramic cast sheet are preferably alumina ceramic cast sheets; the purity is preferably equal to 99.6%, specifically 99.7%, 99.8%, 99.9%; the thickness is preferably 1.5-2mm, specifically 1.6mm, 1.7mm, 1.8mm, 1.9mm.

[0053] In the present invention, drilling is helpful to avoid the phenomenon of ceramic bulging caused by the discharge of impurities during the subsequent sintering process; the through holes obtained by drilling are air holes for the integrated ceramic mechanical arm to evacuate air.

[0054] In the present invention, the temperature of the warm isostatic pressing treatment is 50-80°C, specifically 55°C, 60°C, 65°C, 70°C, and 75°C; the pressure is 8-18MPa, specifically 10MPa, 12MPa, 14MPa, 15MPa, and 16MPa; the time is 5-60min, specifically 8min, 10min, 20min, 30min, 40min, 50min, and 60min.

[0055] Without warm isostatic pressing, the cast sheets cannot be combined together, and even after debinding and sintering, delamination defects will occur. However, too high warm isostatic pressure will also have adverse effects. Due to the difference in stiffness between the lost foam and the cast sheet, too high pressure will cause different deformation amounts in the area with the lost foam and the area with all cast sheets. Since the lost foam material is softer than the cast sheet, it is more likely to produce depressions, which cannot be eliminated by subsequent debinding and sintering processes.

[0056] It should be noted that the process parameters of warm isostatic pressing (pressure, temperature, holding time, etc.) are related to the materials and processes of the lost foam and cast sheet. By adjusting the materials and processes of the lost foam and obtaining a lost foam that is closer to the elastic modulus of the cast sheet, the pressure that can be used for the corresponding warm isostatic pressing can be increased, which helps to deal with some scenes with greater pressing difficulties. Therefore, the warm isostatic process range provided here matches the lost foam used. If the materials and processes of the lost foam are adjusted, the subsequent process parameters need to be adjusted accordingly.

[0057] In the present invention, the debinding step is to place the green body after warm isostatic pressing horizontally, and heat it at 50 to 300° C. for 1 to 8 hours to complete the debinding process.

[0058] In the present invention, during the debinding process, the heating treatment temperature can be 80°C, 100°C, 120°C, 150°C, 180°C, 200°C, 220°C, 250°C, 280°C, and the heating treatment time can be 2h, 3h, 4h, 5h, 6h, 7h.

[0059] In the present invention, the debinding process preferably includes a first debinding process, a second debinding process and a third debinding process performed sequentially;

[0060] The temperature of the first debinding treatment is 50-100°C, specifically 60°C, 70°C, 80°C, 90°C; the time is 1-4h, specifically 1.5h, 2h, 2.5h, 3h, 3.5h;

[0061] The temperature of the second debinding treatment is 120-180°C, specifically 130°C, 140°C, 150°C, 160°C; the time is 1-4h, specifically 1.5h, 2h, 2.5h, 3h, 3.5h;

[0062] The temperature of the third stage of debinding treatment is 180-300°C, specifically 200°C, 220°C, 240°C, 250°C, 260°C, 280°C; the time is 1-3h, specifically 1.5h, 2h, 2.5h;

[0063] The total heating time is 1 to 8 hours.

[0064] In the present invention, the meaning of debinding is to create conditions for densification firing: the debinding process can remove the binder in the green body (the cast sheet contains binder), reduce the gas and impurities that may be generated during the sintering process, thereby facilitating the densification firing of the ceramic and improving the sintering density and strength of the ceramic. Avoid sintering defects: avoid reduction or other chemical reactions of the binder during sintering, thereby affecting the quality of the product, and reduce the occurrence of defects such as cracking and deformation.

[0065] In the present invention, the temperature of the degreasing treatment is 200-450°C, specifically 220°C, 250°C, 280°C, 300°C, 320°C, 350°C, 380°C, 400°C, 420°C; the time of the degreasing sintering treatment is 2-4h, specifically 2.2h, 2.4h, 2.5h, 2.6h, 2.8h, 3h, 3.2h, 3.4h, 3.5h, 3.6h, 3h, 3.8h.

[0066] In the present invention, the significance of degreasing is that the rapid ablation of the lost foam during the sintering process may produce gas, and too fast a speed may cause the model to break or deform. By degreasing, these adverse effects can be reduced. At the same time, the degreasing process also helps to discharge organic additives in the ceramic body. The ceramic body after degreasing is purer, which is conducive to the growth and densification of grains in the subsequent sintering process, thereby optimizing the mechanical properties, thermal properties, etc. of the ceramic.

[0067] In the present invention, the sintering temperature is 1500-1700°C, specifically 1520°C, 1550°C, 1580°C, 1600°C, 1620°C, 1650°C, 1680°C; the sintering time is 1-4h, specifically 1.5h, 2h, 2.5h, 3h, 3.5h.

[0068] The integrated ceramic robot arm of the present invention is used for transporting semiconductor parts (mainly wafers).

[0069] In the present invention, the tape casting lamination preparation method is more efficient. Dry pressing also requires a dry pressing machine, a mold or a CNC groove engraving for air slot positioning. The tape casting sheet can be purchased from outside and then quickly cut out the shape with a laser, which is independent of equipment. The preparation accuracy of this method is also high, and the tape casting can make a minimum groove of 0.1mm.

[0070] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0071] Example 1

[0072] Cut the required ceramic hollow shape (thickness 1mm, purity ≥99%, the thickness of the graphite paper determines the thickness of the hollow pore groove) from the graphite paper by laser cutting as the lost mold; then select the alumina ceramic cast sheet with a purity of 99.6% and a thickness of 2mm (996 alumina ceramic cast sheet, plane size: 192×127mm 2 , shrinkage rate is 0.856), one of which is cut into a hollow shape with the same shape as the lost mold by laser (lost mold = hollow shape × 0.865) as the air slot ceramic cast sheet. Then the lost mold is placed in the hollow of the air slot ceramic cast sheet, and two layers of the cast sheets are set on both sides as the laminated ceramic cast sheet. The whole is pressed at 70°C and 15MPa pressure for 10 minutes, and then the lost mold is punched in the positive projection of the laminated ceramic cast sheet to obtain a green body. The hole is a single-sided hole that connects the outside world with the air slot of the air slot ceramic cast sheet.

[0073] Then the green body obtained above is vacuum packed (to avoid water ingress during warm isostatic pressing), and warm isostatic pressing is performed for 10 minutes in a water bath at 65°C under a pressure of 15MPa; then it is placed on a horizontal plane with a flatness of less than 0.01 (in order to keep the ceramic flat during debinding), and the temperature is raised to 80°C in a drying furnace for 3 hours, and then kept at 150°C for 3 hours, and then kept at 200°C for 2 hours to complete the debinding treatment and discharge excess glue. Then, the green body after debinding is placed on a flat support plate, and corundum sand is evenly sprinkled on the plate, and placed in a kiln, and placed in the center of the sintering furnace to prevent uneven sintering temperature. After degreasing and high-temperature sintering, the graphite paper is burned during the sintering process to obtain a hollow ceramic (integrated ceramic robotic arm). The degreasing temperature is 320°C and the time is 3h; the high-temperature sintering is 1620°C, and the total sintering time is 3h.

[0074] like Figure 1 As shown, the ceramic surface after sintering in this embodiment has no cracks, no color difference, no bubbles, and no stratification. The inner wall of the airway is illuminated and observed to be transparent, without foreign matter, no black spots, and no additional coloring. The ceramic embryo is placed on a 5-micron marble plate for testing, and the flatness of the product is checked with a 3mm plug gauge. The final measurement is: the surface flatness is within 0.05mm, and the air tightness is -95kPa (use the mold to seal the air holes on the arm, evacuate the air tank, and read the value on the barometer to obtain the air tightness data.), which meets the requirements. The density is 3.803g / cm 3 The whole surface is then ground and polished. The F-arm shape is processed by CNC to complete the finished product.

[0075] Break off the arm, Figure 2 As shown, there is no delamination on the side, indicating that the cast sheets are well bonded.

[0076] Example 2

[0077] Cut the required ceramic hollow shape (thickness 1mm, purity ≥99%, the thickness of the graphite paper determines the thickness of the hollow pore groove) from the graphite paper by laser cutting as the lost mold; then select the alumina ceramic cast sheet with a purity of 99.6% and a thickness of 2mm (996 alumina ceramic cast sheet, plane size: 192×127mm 2 , shrinkage rate is 0.856), one of which is cut into a hollow shape with the same shape as the lost mold by laser (lost mold = hollow shape × 0.865) as the air slot ceramic cast sheet. Then the lost mold is placed in the hollow of the air slot ceramic cast sheet, and two layers of the cast sheets are set on both sides as the laminated ceramic cast sheet. The whole is pressed at 50°C and 10MPa pressure for 15min, and then the lost mold is punched in the positive projection of the laminated ceramic cast sheet to obtain a green body. The hole is a single-sided hole that connects the outside world with the air slot of the air slot ceramic cast sheet.

[0078] Then the green body obtained above is vacuum packed (to avoid water ingress during warm isostatic pressing), and warm isostatic pressing is carried out for 20 minutes in a water bath at 80°C under a pressure of 18MPa; then it is placed on a horizontal plane with a flatness of less than 0.01 (in order to keep the ceramic flat during debinding), and the temperature is raised to 100°C in a drying furnace for 2 hours, and then kept at 180°C for 2 hours, and then kept at 300°C for 1 hour to complete the debinding treatment and discharge excess glue. Then, the green body after debinding is placed on a flat support plate, and corundum sand is evenly sprinkled on the plate, and placed in a kiln, and placed in the center of the sintering furnace to prevent uneven sintering temperature. After degreasing and high-temperature sintering, the graphite paper is burned during the sintering process to obtain a hollow ceramic (integrated ceramic robotic arm). The degreasing temperature is 200°C and the time is 2 hours; the high-temperature sintering is 1700°C, and the total sintering time is 4 hours.

[0079] Example 3

[0080] 60g of graphene (Guangdong Quantum Dot New Materials Co., Ltd., carbon content>99%, graphitization degree>99%, black appearance, sheet diameter: 8μm, sheet thickness<5nm, water content<1.0%, bulk density 0.02g / mL), 20mL of pine alcohol, 10mL of methanol, and 10g of ethyl cellulose were mixed and ball-milled for 4 hours to obtain a preliminary mixture. 10g of butyl acetate was added to the preliminary mixture, and ball-milling was continued for 4 hours to obtain a pre-slurry. 10g of dibutyl oxalate was added to the pre-slurry, and stirred for 1 hour to fully mix the components, and the viscosity of the obtained slurry was modulated to obtain a final carbon-based sacrificial slurry with good fluidity (3Pa.S).

[0081] Select an alumina ceramic casting sheet with a purity of 99.6% and a thickness of 2 mm (996 alumina ceramic casting sheet, plane size: 192×127 mm 2 , shrinkage rate is 0.856), one of which is cut into the required hollow shape by laser as an air slot ceramic cast sheet. Then the above-mentioned carbon-based sacrificial slurry is poured into the cut hollow groove until the entire cavity is filled, and then dried at 80 degrees as an expendable mold. Two layers of the above-mentioned cast sheets are set on each side as a laminated ceramic cast sheet, and the whole is pressed at 80°C and 20MPa pressure for 10 minutes, and then the expendable mold is punched in the positive projection of the laminated ceramic cast sheet to obtain a green body. The hole is a single-sided hole that connects the outside world with the air slot of the air slot ceramic cast sheet.

[0082] Then the green body obtained above is vacuum packed (to avoid water ingress during warm isostatic pressing), and warm isostatic pressing is performed for 8 minutes in a water bath at 50°C under a pressure of 8MPa; then it is placed on a horizontal plane with a flatness of less than 0.01 (in order to keep the ceramic flat during debinding), and the temperature is raised to 50°C in a drying furnace for 2 hours, and then kept at 120°C for 3 hours, and then kept at 300°C for 1 hour to complete the debinding treatment and discharge excess glue. Then, the green body after debinding is placed on a flat support plate, and corundum sand is evenly sprinkled on the plate, and placed in a kiln, and placed in the center of the sintering furnace to prevent uneven sintering temperature. After degreasing and high-temperature sintering, the graphite paper is burned during the sintering process to obtain a hollow ceramic (integrated ceramic robotic arm). The degreasing temperature is 400°C and the time is 2 hours; the high-temperature sintering is 1500, and the total sintering time is 1 hour.

[0083] Comparative Examples 1 to 3

[0084] The difference between Comparative Examples 1 to 3 and Example 1 is only that no warm isostatic pressing treatment is performed or the warm isostatic pressing treatment parameters are adjusted.

[0085] Serial number pressure temperature time Comparative Example 1 0 0 0 Comparative Example 2 30MPa 60℃ 10 / min Comparative Example 3 25MPa 60℃ 10 / min

[0086] Comparative Example 1 shows the case where no warm isostatic pressing treatment is performed, and the obtained mechanical arm is as follows Figure 3 As shown. The interface left by the original cast film can still be clearly observed on the side. The existence of this delamination phenomenon will lead to a reduction in the service life of the arm and reduced air tightness.

[0087] Comparative Example 2 The temperature isostatic pressure is 30 MPa, and the hot pressing is performed at 60°C for 10 minutes. After the hot pressing is completed, depressions and cracks are observed in the hollow part. Figure 4 As shown, it can be seen that there is an obvious depression in the area filled by the lost foam, which leads to cracking along the edge of the area.

[0088] In comparative example 3, the isostatic pressure is 25 MPa, and hot pressing is performed at 60°C for 10 minutes. After the hot pressing is completed, obvious depressions can be observed in the hollow parts. The depressions cannot be eliminated by subsequent processes, which will have an adverse effect on the surface flatness of the final product.

[0089] The various embodiments in this specification are described in a progressive manner, and each embodiment focuses on the differences from other embodiments. The same or similar parts between the various embodiments can be referenced to each other.

[0090] The above description of the disclosed embodiments enables one skilled in the art to implement or use the present invention. Various modifications to these embodiments will be apparent to one skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to the embodiments shown herein, but rather to the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A method for preparing a tape-cast laminate of an integrated ceramic robot arm, characterized in that: The steps include: 1) preparing an evaporative mold, and preparing a ceramic cast sheet with an air groove having the same shape as the evaporative mold according to the shape of the evaporative mold; 2) placing the lost mold in the hollow of the air slot ceramic cast sheet, arranging the overlapping ceramic cast sheets on both sides, and obtaining the green body after punching; 3) The green body obtained in step 2) is subjected to warm isostatic pressing, binder removal, and degreasing and sintering in sequence to obtain an integrated ceramic robotic arm.

2. The method for preparing a tape-cast laminate of an integrated ceramic robot arm according to claim 1, characterized in that: The lost mold includes graphite paper or carbon-based sacrificial slurry.

3. The method for preparing a tape-cast laminate of an integrated ceramic robot arm according to claim 2, characterized in that: The method for preparing the carbon-based sacrificial slurry comprises the following steps: The carbon material, the high boiling point solvent, the low boiling point solvent and the dispersing binder are mixed and ball-milled to obtain a preliminary mixture; The preliminary mixture is mixed with a diluent solvent and ball-milled to obtain a pre-slurry; the pre-slurry is mixed with a slurry modifier and stirred to obtain a carbon-based sacrificial slurry.

4. The method for preparing a tape-cast laminate of an integrated ceramic robot arm according to claim 3, characterized in that: The carbon material includes one or more of carbon black, graphite powder and graphene; and / or The high boiling point solvent includes terpineol and / or ethylene glycol butyl ether; and / or The low boiling point solvent comprises methanol and / or ethanol; and / or The dispersed binder includes one or more of vinyl, cellulose and acrylic resins; and / or The dilution solvent comprises one or more of butyl acetate, methyl acetate, ethyl acetate and n-propyl acetate; and / or The slurry modifier includes one or more of a defoamer, a thixotropic agent and a leveling agent.

5. The method for preparing a tape-cast laminate of an integrated ceramic robot arm according to claim 4, characterized in that: The volume of the lost mold = the hollowing out of the air slot ceramic cast sheet × the shrinkage rate of the air slot ceramic cast sheet.

6. The tape casting lamination preparation method of the integrated ceramic robot arm according to any one of claims 1 to 5, characterized in that: The position of the punching hole in step 2) is located within the orthographic projection of the lost mold on the laminated ceramic cast sheet.

7. The method for preparing a tape-cast laminate of an integrated ceramic robot arm according to claim 6, characterized in that: The parameters of the warm isostatic pressing process include: The temperature is 50-80°C; and / or The pressure is 8-18 MPa; and / or The time is 5 to 60 minutes.

8. The method for preparing a tape-cast laminate of an integrated ceramic robot arm according to claim 7, characterized in that: The debinding process comprises: The green body after warm isostatic pressing is placed horizontally; Heat at 50-300°C for 1-8h.

9. The tape casting lamination preparation method of the integrated ceramic robot arm according to claim 7 or 8, characterized in that: The parameters of the degreasing process include: The temperature is 200 to 450°C; and / or The time is 2 to 4 hours.

10. The method for preparing a tape-cast laminate of an integrated ceramic robot arm according to claim 9, characterized in that: The parameters of the sintering process include: The temperature is 1500-1700°C; and / or The time is 1 to 4 hours.

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