3D printing high-entropy ceramic and preparation process thereof

Abstract

The invention discloses a 3D printing high-entropy ceramic which is prepared from the following components in percentage by mass: 15-20% of aluminum oxide, 8-10% of nickel oxide, 15-20% of silicon dioxide, 10-15% of yttrium oxide, 10-15% of zirconium dioxide, 10-15% of hafnium oxide, 8-10% of magnesium oxide and 8-10% of auxiliaries, a preparation process comprises the following steps: step 1, preparing ceramic powder, step 2, preparing slurry, step 3, preparing the 3D printing high-entropy ceramic, and step 4, preparing the 3D printing high-entropy ceramic. 3, printing and drying treatment; 4, high-temperature sintering treatment; and 5, sintering post-treatment. Rapid forming can be achieved through the 3D printing technology, meanwhile, forming preparation of ceramic parts with extremely complex shapes can be achieved, the manufacturing period is effectively shortened, material waste and the manufacturing cost are remarkably reduced, meanwhile, through improvement of materials such as aluminum oxide and silicon dioxide, the density of the high-entropy ceramic can be effectively improved, and the high-entropy ceramic is obtained. Therefore, the mechanical property and the thermal stability are improved, and high-end application requirements are met.

Description

Technical Field

[0001] The present invention relates to the technical field of high entropy ceramics, and in particular to a 3D printed high entropy ceramic and a preparation process thereof. Background Art

[0002] High entropy ceramics are a new type of multi-principal amorphous alloy. Due to their unique microstructure and chemical composition, they exhibit many excellent properties such as high strength, high hardness, good thermal stability and chemical stability.

[0003] However, the traditional high-entropy ceramic preparation method has the problems of high cost, low efficiency, and difficulty in preparing complex shapes. At the same time, the components and dosage of high-entropy ceramic materials are the key influencing factors affecting the performance of high-entropy ceramics. Therefore, the present invention proposes a 3D printed high-entropy ceramic and a preparation process thereof to solve the problems existing in the prior art. Summary of the invention

[0004] In view of the above problems, the purpose of the present invention is to propose a 3D printed high-entropy ceramic and its preparation process. The 3D printed high-entropy ceramic and its preparation process adopt 3D printing technology to achieve rapid prototyping, and at the same time, can realize the forming and preparation of extremely complex shaped ceramic parts, effectively shorten the manufacturing cycle, and significantly reduce material waste and manufacturing costs. At the same time, through the improvement of materials such as alumina and silica, the density of high-entropy ceramics can be effectively improved, thereby improving mechanical properties and thermal stability to meet high-end application requirements.

[0005] To achieve the purpose of the present invention, the present invention is implemented through the following technical scheme: a 3D printed high-entropy ceramic, the raw materials comprising aluminum oxide, nickel oxide, silicon dioxide, yttrium oxide, zirconium dioxide, hafnium dioxide, magnesium oxide and additives in mass percentages of 15-20%, 8-10%, 15-20%, 10-15%, 10-15%, 10-15%, 8-10%, and 8-10%, wherein the additives include a binder, a plasticizer, a dispersant and a solvent.

[0006] A further improvement is that the binder is one or more of polyacrylate, cetyl ethylhexanoate, sodium alginate, paraffin and dimethyl silicone oil; and the plasticizer is one of siloxane, epoxy resin, acrylate, glyceride and fatty acid amide.

[0007] A further improvement is that: the dispersant is one or more of polyvinyl pyridone, sodium polyacrylate, ammonium polyacrylate, polyethyleneimine and KOS110 dispersant; and the solvent is water.

[0008] A preparation process for 3D printing high entropy ceramics, comprising the following steps:

[0009] Step 1, ceramic powder preparation, firstly, aluminum oxide, nickel oxide, silicon dioxide, yttrium oxide, zirconium dioxide, hafnium dioxide and magnesium oxide are uniformly mixed according to the proportion, and then the mixture is added into an ultra-fine grinder for grinding to obtain a ceramic powder raw material;

[0010] Step 2, slurry preparation, first adding the ceramic powder raw material into the solvent for mixing, then adding the dispersant for mixing and stirring, and then adding it into a homogenizer for high pressure homogenization to obtain a mixed solution, and then adding the binder and plasticizer into the mixed solution for sufficient stirring to obtain a printing slurry;

[0011] Step 3: Printing and drying treatment: adding the printing slurry into a multi-axis 3D printing device, printing a green body layer by layer according to the required model data, and drying and shaping it to obtain a solidified green body;

[0012] Step 4: high temperature sintering treatment, placing the solidified green body in a spark plasma sintering device for sintering, removing organic matter and additives and causing the ceramic powder raw materials to undergo a sintering reaction to form a dense high entropy ceramic body;

[0013] Step 5: Post-sintering treatment: After sintering, the high entropy ceramic body is tempered, and after tempering, its surface is finely polished to obtain a high entropy ceramic.

[0014] A further improvement is that: during the grinding in step 1, the mixed material is added to water and stirred by a wet grinding method, and then the mixed aqueous solution is added to an ultrafine grinder for grinding, and finally the ground material is dried under inert gas conditions at 120-160°C for 15-20 minutes to obtain a powder; the powder after being processed by the ultrafine grinder needs to be screened with 400 mesh to obtain a ceramic powder raw material with a particle size less than or equal to 38μm.

[0015] Further improvements are: the pressure set for the high-pressure homogenization treatment in step 2 is 180 MPa and the flow rate is 6.5 L / h; after the binder and plasticizer are added in step 2, the mixed liquid is fully mixed and stirred by ball milling.

[0016] Further improvements are: during printing in step three, printing is performed in an environment where the binder can be quickly cured; after printing, drying is performed at a temperature of 85-110° C. for 14-16 hours; after drying, the green body is degreased at a temperature of 350-550° C. for 1-2 hours using a thermal degreasing method to obtain a cured green body.

[0017] A further improvement is that the sintering conditions for the solidified green body in step 4 are to sinter at a temperature of 1300-1600°C for 2-3 hours under pressureless conditions in a spark plasma sintering device. During sintering, the device is first preheated to 300-600°C, then the green body is placed in it and the temperature is increased to 1300-1600°C at a heating rate of 10-15°C / min.

[0018] A further improvement is that the tempering treatment in step five is to place the sintered high entropy ceramic body in a vacuum environment at a temperature of 800-1200° C. for tempering for 12-15 hours.

[0019] The beneficial effects of the present invention are as follows: the present invention can realize rapid prototyping by using 3D printing technology, and can realize the molding and preparation of ceramic parts with extremely complex shapes, effectively shorten the manufacturing cycle, and significantly reduce material waste and manufacturing costs. At the same time, through the improvement of materials such as alumina and silica, the density of high-entropy ceramics can be effectively improved, thereby improving mechanical properties and thermal stability to meet high-end application requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 The figure is a flow chart of the method of the present invention. DETAILED DESCRIPTION

[0021] In order to deepen the understanding of the present invention, the present invention will be further described in detail below in conjunction with examples. The examples are only used to explain the present invention and do not constitute a limitation on the protection scope of the present invention.

[0022] The present embodiment provides a 3D printed high entropy ceramic, wherein the raw materials include aluminum oxide, nickel oxide, silicon dioxide, yttrium oxide, zirconium dioxide, hafnium dioxide, magnesium oxide and additives in weight percentages of 15-20%, 8-10%, 15-20%, 10-15%, 10-15%, 10-15%, 8-10%, and 8-10%, wherein the additives include a binder, a plasticizer, a dispersant and a solvent.

[0023] The binder is one or more of polyacrylate, cetyl ethylhexanoate, sodium alginate, paraffin and dimethyl silicone oil; the plasticizer is one of siloxane, epoxy resin, acrylate, glyceride and fatty acid amide; the dispersant is one or more of polyvinyl pyridone, sodium polyacrylate, ammonium polyacrylate, polyethylene imine and KOS110 dispersant; and the solvent is water.

[0024] Example 1

[0025] according to Figure 1 As shown, this embodiment provides a preparation process for 3D printing high entropy ceramics, which is characterized by comprising the following steps:

[0026] Step 1, ceramic powder preparation, first according to the mass percentage of 20% aluminum oxide, 10% nickel oxide, 20% silicon dioxide, 10% yttrium oxide, 10% zirconium dioxide, 10% hafnium dioxide and 10% magnesium oxide are uniformly mixed, and then the mixture is added to the ultrafine grinder for grinding to obtain a ceramic powder raw material;

[0027] The powder is ground by adding the mixed material into water using a wet grinding method and stirring it. The mixed aqueous solution is then added into an ultrafine grinder for grinding. Finally, the ground material is dried under an inert gas condition of 160° C. for 15 minutes to obtain a powder. The powder after being processed by the ultrafine grinder needs to be screened through 400 mesh to obtain a ceramic powder raw material with a particle size of less than or equal to 38 μm.

[0028] Step 2, slurry preparation, first add the ceramic powder raw material into water for mixing, then add KOS110 dispersant for mixing and stirring, and then add it into a homogenizer, set the pressure to 180MPa and the flow rate to 6.5L / h for high-pressure homogenization to obtain a mixed solution, then add cetyl ethylhexanoate and glyceride into the mixed solution and stir it thoroughly to obtain a printing slurry;

[0029] After cetyl ethylhexanoate and glyceride are added, the mixed solution is fully mixed and stirred by ball milling.

[0030] The mass percentage of water, KOS110 dispersant, cetyl ethylhexanoate and glycerol in the additive and the total amount of raw materials of high entropy ceramics is 10%, and the mass percentages of water, KOS110 dispersant, cetyl ethylhexanoate and glycerol in the additive are 60%, 15%, 10% and 15% respectively.

[0031] Step 3: Printing and drying treatment: adding the printing slurry into a multi-axis 3D printing device, printing a green body layer by layer according to the required model data, and drying and shaping it to obtain a solidified green body;

[0032] The printing is performed in an ultraviolet irradiation environment where cetyl ethylhexanoate can be quickly cured; after printing, the green body is dried at 85°C for 16 hours; after drying, the green body is degreased at 500°C for 1.5 hours using a thermal degreasing method to obtain a cured green body.

[0033] Step 4: high temperature sintering treatment, placing the solidified green body in a spark plasma sintering device for sintering, removing organic matter and additives and causing the ceramic powder raw materials to undergo a sintering reaction to form a dense high entropy ceramic body;

[0034] The sintering conditions are as follows: sintering at 1450°C for 3 hours under pressureless conditions in a spark plasma sintering device. During sintering, the device is first preheated to 300°C, then the green body is placed in it and the temperature is increased to 1450°C at a heating rate of 12°C / min.

[0035] Step 5: Post-sintering treatment: After sintering, the high entropy ceramic body is tempered, and after tempering, the surface is finely polished to obtain a high entropy ceramic;

[0036] The tempering treatment specifically involves placing the sintered high entropy ceramic body in a vacuum environment at 950° C. for tempering for 14.5 hours.

[0037] The density and shrinkage rate of the product prepared in this embodiment were tested, and the density of the product was found to be 96.8%, and the shrinkage rate of the product was 4.55% compared with the green body.

[0038] Example 2

[0039] according to Figure 1 As shown, this embodiment provides a preparation process for 3D printing high entropy ceramics, which is characterized by comprising the following steps:

[0040] Step 1, ceramic powder preparation, first according to the mass percentage of 15% aluminum oxide, 10% nickel oxide, 15% silicon dioxide, 15% yttrium oxide, 15% zirconium dioxide, 10% hafnium dioxide and 10% magnesium oxide are uniformly mixed, and then the mixture is added to an ultrafine grinder and ground to obtain a ceramic powder raw material;

[0041] The powder is ground by adding the mixed material into water using a wet grinding method and stirring it. The mixed aqueous solution is then added into an ultrafine grinder for grinding. Finally, the ground material is dried under an inert gas condition of 120°C for 20 minutes to obtain a powder. The powder after being processed by the ultrafine grinder needs to be screened through 400 mesh to obtain a ceramic powder raw material with a particle size of less than or equal to 38 μm.

[0042] Step 2, slurry preparation, first add the ceramic powder raw material into water and mix, then add polyvinyl pyridone, mix and stir, and then add it into a homogenizer, set the pressure to 180MPa and the flow rate to 6.5L / h for high-pressure homogenization to obtain a mixed solution, then add polyacrylate and fatty acid amide into the mixed solution and stir it thoroughly to obtain a printing slurry;

[0043] After the polyacrylate and fatty acid amide are added, the mixed solution is fully mixed and stirred by ball milling.

[0044] The mass percentage of water, polyvinyl pyridone, polyacrylate and fatty acid amide constituting the auxiliary agent to the total amount of raw materials of the high entropy ceramic is 10%, and the mass percentages of water, polyvinyl pyridone, polyacrylate and fatty acid amide in the auxiliary agent are 50%, 20%, 10% and 20% respectively.

[0045] Step 3: Printing and drying treatment: adding the printing slurry into a multi-axis 3D printing device, printing a green body layer by layer according to the required model data, and drying and shaping it to obtain a solidified green body;

[0046] The printing is performed in an ultraviolet irradiation environment where cetyl ethylhexanoate can be quickly cured; after printing, it is dried at 100°C for 16 hours; after drying, the green body is degreased at 400°C for 2 hours using a thermal degreasing method to obtain a cured green body.

[0047] Step 4: high temperature sintering treatment, placing the solidified green body in a spark plasma sintering device for sintering, removing organic matter and additives and causing the ceramic powder raw materials to undergo a sintering reaction to form a dense high entropy ceramic body;

[0048] The sintering conditions are as follows: sintering at 1600°C for 2 hours under pressureless conditions in a spark plasma sintering device. During sintering, the device is first preheated to 500°C, then the green body is placed in it and the temperature is increased to 1600°C at a heating rate of 10°C / min.

[0049] Step 5: Post-sintering treatment: After sintering, the high entropy ceramic body is tempered, and after tempering, the surface is finely polished to obtain a high entropy ceramic;

[0050] The tempering treatment specifically involves placing the sintered high entropy ceramic body in a vacuum environment at a temperature of 1100° C. for tempering for 15 hours.

[0051] The density and shrinkage rate of the product prepared in this example were tested, and the density of the product was found to be 97.4%, and the shrinkage rate of the product was 3.65% compared with the green body.

[0052] Reasonable temperature control and slow sintering heating rate can reduce the stress generated during sintering. At the same time, the tempering temperature and duration will also affect the density and strength of the product. It can be seen from the products prepared in the above-mentioned Examples 1 and 2 that the performance of the prepared product is better than that of the product in Example 1 by mixing the mass percentages of the components in Example 2 and sintering at a reasonable temperature and heating rate, indicating that the mass percentages of the components and the sintering conditions in Example 2 are optimal.

[0053] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments. The above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. A 3D printed high entropy ceramic, characterized in that: The raw materials include aluminum oxide, nickel oxide, silicon dioxide, yttrium oxide, zirconium dioxide, hafnium dioxide, magnesium oxide and additives in percentage by mass of 15-20%, 8-10%, 15-20%, 10-15%, 10-15%, 10-15%, 8-10% and 8-10%, wherein the additives include binders, plasticizers, dispersants and solvents.

2. A 3D printed high entropy ceramic according to claim 1, characterized in that: The binder is one or more of polyacrylate, cetyl ethylhexanoate, sodium alginate, paraffin and dimethyl silicone oil; the plasticizer is one of siloxane, epoxy resin, acrylate, glyceride and fatty acid amide.

3. A 3D printed high entropy ceramic according to claim 1, characterized in that: The dispersant is one or more of polyvinyl pyridone, sodium polyacrylate, ammonium polyacrylate, polyethyleneimine and KOS110 dispersant; and the solvent is water.

4. A preparation process for 3D printed high entropy ceramics, characterized in that: The following steps are involved: Step 1, ceramic powder preparation, firstly, aluminum oxide, nickel oxide, silicon dioxide, yttrium oxide, zirconium dioxide, hafnium dioxide and magnesium oxide are uniformly mixed according to the proportion, and then the mixture is added into an ultra-fine grinder for grinding to obtain a ceramic powder raw material; Step 2, slurry preparation, first adding the ceramic powder raw material into the solvent for mixing, then adding the dispersant for mixing and stirring, and then adding it into a homogenizer for high pressure homogenization to obtain a mixed solution, and then adding the binder and plasticizer into the mixed solution for sufficient stirring to obtain a printing slurry; Step 3: Printing and drying treatment: adding the printing slurry into a multi-axis 3D printing device, printing a green body layer by layer according to the required model data, and drying and shaping it to obtain a solidified green body; Step 4: high temperature sintering treatment, placing the solidified green body in a spark plasma sintering device for sintering, removing organic matter and additives and causing the ceramic powder raw materials to undergo a sintering reaction to form a dense high entropy ceramic body; Step 5: Post-sintering treatment: After sintering, the high entropy ceramic body is tempered, and after tempering, its surface is finely polished to obtain a high entropy ceramic.

5. A preparation process for 3D printed high entropy ceramics according to claim 4, characterized in that: In the step 1, the mixed material is added into water and stirred by wet grinding, and then the mixed aqueous solution is added into an ultrafine grinder for grinding, and finally the ground material is dried under an inert gas condition of 120-160° C. for 15-20 minutes to obtain a powder; the powder after being processed by the ultrafine grinder needs to be screened through 400 mesh to obtain a ceramic powder raw material with a particle size of less than or equal to 38 μm.

6. A preparation process for 3D printed high entropy ceramics according to claim 4, characterized in that: The pressure set for the high-pressure homogenization treatment in step 2 is 180 MPa and the flow rate is 6.5 L / h; after the binder and plasticizer are added in step 2, the mixed solution is fully mixed and stirred by ball milling.

7. A preparation process for 3D printed high entropy ceramics according to claim 4, characterized in that: During the printing in step 3, printing is performed in an environment where the binder can be quickly cured; After printing, the green body is dried at 85-110° C. for 14-16 hours; after drying, the green body is degreased at 350-550° C. for 1-2 hours using a thermal degreasing method to obtain a solidified green body.

8. A preparation process for 3D printed high entropy ceramics according to claim 4, characterized in that: The sintering conditions for solidifying the green body in step 4 are sintering at a temperature of 1300-1600° C. for 2-3 hours in a spark plasma sintering device under pressureless conditions. During sintering, the device is first preheated to 300-600° C., then the green body is placed in it and the temperature is increased to 1300-1600° C. at a heating rate of 10-15° C. / min.

9. A preparation process for 3D printed high entropy ceramics according to claim 4, characterized in that: The tempering treatment in step 5 is specifically to place the sintered high entropy ceramic body in a vacuum environment at a temperature of 800-1200° C. for tempering for 12-15 hours.

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