High-entropy ceramic powder for 3D printing and preparation method thereof

Abstract

The invention discloses high-entropy ceramic powder for 3D printing and a preparation method of the high-entropy ceramic powder, and relates to the technical field of 3D printing materials, and the high-entropy ceramic powder comprises the following raw materials: composite ceramic powder, composite metal oxide, thermoplastic powder, an adhesive, a coupling agent and a surface modifier; the high-entropy ceramic powder prepared by taking the composite ceramic powder as a main material, taking the composite metal oxide as an auxiliary material and adding the thermoplastic plastic powder as a filling material is high in bulk density, uniform in particle and relatively high in hardness and strength, so that a prepared 3D printing product has good toughness and impact strength, and the 3D printing product contains various elements, so that the 3D printing product has good toughness and impact strength. The high-entropy ceramic obtained through 3D printing has high mixing entropy, the crystal structure of the material is stabilized, the physical performance of the material is improved, in addition, the microstructure of ceramic powder can be effectively improved by conducting segmented calcination on the ball-milled mixture in the preparation process, and therefore the mechanical strength of a subsequent 3D printing ceramic product is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of 3D printing materials, and in particular to a high entropy ceramic powder for 3D printing and a preparation method thereof. Background Art

[0002] 3D printing, also known as additive manufacturing, is a technology that constructs three-dimensional objects by stacking materials layer by layer. It can use a variety of materials such as plastics, metals, ceramics, etc. to manufacture complex parts and products based on digital models. It is widely used in medical, aerospace, automotive and construction industries. With the development of new materials and the advancement of printing technology, 3D printing is expected to play a greater role in personalized medicine, intelligent manufacturing, remote construction and other fields. At the same time, as costs decrease and efficiency increases, 3D printing technology will become more popular and become an indispensable part of modern manufacturing.

[0003] 3D printing materials are an indispensable part of 3D printing technology. Their types, characteristics and uses directly affect the quality and application scope of the printed products. Among them, ceramic powder is an indispensable material in 3D printing technology, especially in the manufacture of ceramic parts with complex shapes and fine structures. The particle size, shape, distribution and chemical composition of ceramic powder will affect the 3D printing process and the performance of the final product.

[0004] Most of the existing ceramic powders used for 3D printing have a single component. The prepared ceramic powder has a low bulk density and is prone to agglomeration. In addition, the printed products obtained after 3D printing are lacking in physical properties and do not have good toughness and impact resistance. The quality of the printed products needs to be improved. Therefore, the present invention proposes a high-entropy ceramic powder for 3D printing and a preparation method thereof to solve the problems existing in the prior art. Summary of the invention

[0005] In view of the above problems, the purpose of the present invention is to propose a high-entropy ceramic powder for 3D printing and a preparation method thereof, so as to solve the problems that the existing ceramic powder used for 3D printing has a single composition, the prepared ceramic powder has a low bulk density, is prone to agglomeration, and the printed products obtained after 3D printing are lacking in physical properties and do not have good toughness and impact performance.

[0006] In order to achieve the purpose of the present invention, the present invention is implemented through the following technical scheme: a high entropy ceramic powder for 3D printing, comprising the following raw materials in parts by weight: 40 to 50 parts of composite ceramic powder, 20 to 30 parts of composite metal oxide, 10 to 15 parts of thermoplastic plastic powder, 3 to 5 parts of adhesive, 5 to 7 parts of coupling agent and 5 to 10 parts of surface modifier.

[0007] A further improvement is that the composite ceramic powder is composed of a mixture of modified calcite powder, mullite powder, silicon carbide powder and boron nitride powder, and the mixing mass ratio of the modified calcite powder, mullite powder, silicon carbide powder and boron nitride powder is 2-3:2:1:1.

[0008] A further improvement is that the composite metal oxide is composed of a mixture of aluminum oxide powder, zirconium oxide powder and magnesium oxide powder, and the mixing mass ratio of the aluminum oxide powder, zirconium oxide powder and magnesium oxide powder is 1 to 2:1:1.

[0009] A further improvement is that the thermoplastic plastic powder is composed of a mixture of polyamide powder, polycarbonate powder and polyethylene powder, and the mixing mass ratio of the polyamide powder, polycarbonate powder and polyethylene powder is 1 to 2:1:1.

[0010] A further improvement is that the adhesive is selected from one of epoxy resin powder and polyurethane powder, the coupling agent is a silane coupling agent, and the surface modifier is nano silicon dioxide.

[0011] A method for preparing high entropy ceramic powder for 3D printing comprises the following steps:

[0012] Step 1: Weigh 40-50 parts of composite ceramic powder, 20-30 parts of composite metal oxide, 10-15 parts of thermoplastic powder, 3-5 parts of adhesive, 5-7 parts of coupling agent and 5-10 parts of surface modifier respectively, and store them separately for future use;

[0013] Step 2: ball milling the composite ceramic powder, composite metal oxide, thermoplastic powder and surface modifier by wet ball milling, adding a binder and a coupling agent to continue ball milling to obtain a ball milled mixture, and then drying the ball milled mixture;

[0014] Step 3: First, the ball-milled mixture after drying is screened with a sieve, and the powder with qualified particle size obtained by screening is added into a calcining furnace for staged calcination. After calcination, it is naturally cooled to room temperature to obtain a high-entropy ceramic powder semi-finished product;

[0015] Step 4: First, the high entropy ceramic powder semi-finished product is ground by a grinding machine. After the grinding is completed, the powder is evenly spread on a sieve for sieving, and the sieved powder is collected to obtain a high entropy ceramic powder finished product.

[0016] The further improvement is that: in the step 2, the ball mill used in the wet ball milling process is selected from one of steel balls or ceramic balls, and the ball-to-material mass ratio is 1 to 2:1; the liquid ball milling medium used in the wet ball milling process is anhydrous ethanol; the ball milling time of the composite ceramic powder, composite metal oxide, thermoplastic plastic powder and surface modifier is 12 to 16 hours; the ball milling time after adding the adhesive and coupling agent is 1 to 2 hours; the ball mill speed is 500 to 900 r / min.

[0017] A further improvement is that in the step 2, the ball-milled mixture is placed in a drying box and dried at a heating temperature of 60 to 80° C. for 1 to 2 hours.

[0018] A further improvement is that in the step three, the powder with qualified particle size obtained by screening is first calcined at a temperature environment of 300-450°C, then calcined at a temperature environment of 450-600°C, then calcined at a temperature environment of 600-850°C for a third time, then calcined at a temperature environment of 850-1000°C for a fourth time, and finally calcined at a temperature environment of 1000-1150°C for a fifth time.

[0019] The beneficial effects of the present invention are as follows: the high-entropy ceramic powder prepared by the present invention using composite ceramic powder as a main material, composite metal oxide as an auxiliary material, and adding thermoplastic plastic powder as a filler has a high bulk density, uniform particles, high hardness and strength, so that the prepared 3D printed products have good toughness and impact strength, and because it contains multiple elements, the 3D printed high-entropy ceramics have a higher mixing entropy, which helps to stabilize the crystal structure of the material and improve its physical properties. In addition, in the preparation process, each material is ball-milled by wet ball milling, which is helpful for the dispersion and refinement of the material, and by staged calcination of the ball-milled mixture, the microstructure of the ceramic powder can be effectively improved, thereby improving the mechanical strength of subsequent 3D printed ceramic products. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] 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 some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0021] Figure 1 It is a schematic flow chart of a method for preparing high entropy ceramic powder for 3D printing of the present invention. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. 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.

[0023] Embodiment 1

[0024] The present embodiment provides a high entropy ceramic powder for 3D printing, comprising the following raw materials in parts by weight: 40 parts of composite ceramic powder, 30 parts of composite metal oxide, 10 parts of thermoplastic plastic powder, 3 parts of epoxy resin powder, 7 parts of silane coupling agent and 10 parts of nano-silicon dioxide, wherein the composite ceramic powder is composed of modified calcite powder, mullite powder, silicon carbide powder and boron nitride powder mixed in a mass ratio of 2:2:1:1, the composite metal oxide is composed of aluminum oxide powder, zirconium oxide powder and magnesium oxide powder mixed in a mass ratio of 1:1:1, and the thermoplastic plastic powder is composed of polyamide powder, polycarbonate powder and polyethylene powder mixed in a mass ratio of 1:1:1.

[0025] See also Figure 1 This embodiment also provides a method for preparing high entropy ceramic powder for 3D printing, comprising the following steps:

[0026] Step 1: Weigh the raw materials

[0027] First, 40 parts of composite ceramic powder, 30 parts of composite metal oxide, 10 parts of thermoplastic powder, 3 parts of adhesive, 7 parts of coupling agent and 10 parts of surface modifier are weighed by weighing equipment according to the following mass ratios, and are placed in sealed containers for temporary storage;

[0028] Step 2: Ball milling of raw materials

[0029] First, the composite ceramic powder, composite metal oxide, thermoplastic powder and surface modifier are ball-milled for 12 hours by wet ball milling, the ball mill is a steel ball, the ball-to-material mass ratio is 1:1, the liquid ball milling medium is anhydrous ethanol, the ball mill speed is 500r / min, and then an adhesive and a coupling agent are added to continue ball milling for 1 hour to obtain a ball-milled mixture, and then the ball-milled mixture is placed in a drying box and dried at a heating temperature of 60°C for 1 hour. The wet ball milling method is used to ball mill the pre-prepared materials, which can reduce dust flying and reduce heat generation during the grinding process while achieving preliminary grinding of the materials, and also helps to disperse and refine the materials;

[0030] Step 3: Calcination of raw materials

[0031] First, the ball-milled mixture after drying in step 2 is screened with a sieve, and the powder with qualified particle size obtained by screening is added to a calcining furnace for staged calcination, first calcining at a temperature environment of 300°C, then calcining at a temperature environment of 450°C, then calcining at a temperature environment of 600°C for a third time, then calcining at a temperature environment of 850°C for a fourth time, and finally calcining at a temperature environment of 1000°C for a fifth time. After calcination, it is naturally cooled to room temperature to obtain a high-entropy ceramic powder semi-finished product. By calcining the ball-milled mixture in stages, the staged heat treatment of the powder is achieved, the microstructure and performance of the powder can be controlled, and the microstructure of the ceramic powder can be effectively improved, thereby improving the mechanical strength, thermal stability and chemical stability of subsequent 3D printed ceramic products;

[0032] Step 4: Grind and sieve the raw materials

[0033] First, a grinding machine is used to grind the high-entropy ceramic powder semi-finished product obtained in step three to further refine the particle size of the high-entropy ceramic powder semi-finished product. After grinding, the powder is evenly sprinkled on a sieve for sieving, and the sieved powder is collected to obtain a high-entropy ceramic powder product. The powder that has not been sieved is re-grinded until the particle size is qualified.

[0034] Embodiment 2

[0035] The present embodiment provides a high entropy ceramic powder for 3D printing, comprising the following raw materials in parts by weight: 50 parts of composite ceramic powder, 20 parts of composite metal oxide, 15 parts of thermoplastic plastic powder, 5 parts of polyurethane powder, 5 parts of silane coupling agent and 5 parts of nano-silicon dioxide, wherein the composite ceramic powder is composed of modified calcite powder, mullite powder, silicon carbide powder and boron nitride powder mixed in a mass ratio of 3:2:1:1, the composite metal oxide is composed of aluminum oxide powder, zirconium oxide powder and magnesium oxide powder mixed in a mass ratio of 2:1:1, and the thermoplastic plastic powder is composed of polyamide powder, polycarbonate powder and polyethylene powder mixed in a mass ratio of 2:1:1.

[0036] See also Figure 1 This embodiment also provides a method for preparing high entropy ceramic powder for 3D printing, comprising the following steps:

[0037] Step 1: Weigh the raw materials

[0038] First, 50 parts of composite ceramic powder, 20 parts of composite metal oxide, 15 parts of thermoplastic powder, 5 parts of adhesive, 5 parts of coupling agent and 5 parts of surface modifier are weighed by weighing equipment according to the following mass ratios, and are placed in sealed containers for temporary storage;

[0039] Step 2: Ball milling of raw materials

[0040] First, the composite ceramic powder, composite metal oxide, thermoplastic powder and surface modifier are ball-milled for 16 hours by wet ball milling, the ball mill is a ceramic ball, the ball-to-material mass ratio is 2:1, the liquid ball milling medium is anhydrous ethanol, the ball mill speed is 900r / min, and then an adhesive and a coupling agent are added to continue ball milling for 2 hours to obtain a ball-milled mixture, and then the ball-milled mixture is placed in a drying box and dried at a heating temperature of 80°C for 2 hours. The wet ball milling method is used to ball mill the pre-prepared materials, which can reduce dust flying while achieving preliminary grinding of each material, reduce heat generation during the grinding process, and also help disperse and refine the materials;

[0041] Step 3: Calcination of raw materials

[0042] First, the ball-milled mixture after drying in step 2 is screened with a sieve, and the powder with qualified particle size obtained by screening is added to a calcining furnace for staged calcination, first calcining at a temperature environment of 450°C, then calcining at a temperature environment of 600°C, then calcining at a temperature environment of 850°C for a third time, then calcining at a temperature environment of 1000°C for a fourth time, and finally calcining at a temperature environment of 1150°C for a fifth time. After calcination, it is naturally cooled to room temperature to obtain a high-entropy ceramic powder semi-finished product. By calcining the ball-milled mixture in stages, the staged heat treatment of the powder is achieved, the microstructure and performance of the powder can be controlled, and the microstructure of the ceramic powder can be effectively improved, thereby improving the mechanical strength, thermal stability and chemical stability of subsequent 3D printed ceramic products;

[0043] Step 4: Grind and sieve the raw materials

[0044] First, a grinding machine is used to grind the high-entropy ceramic powder semi-finished product obtained in step three to further refine the particle size of the high-entropy ceramic powder semi-finished product. After grinding, the powder is evenly sprinkled on a sieve for sieving, and the sieved powder is collected to obtain a high-entropy ceramic powder product. The powder that has not been sieved is re-grinded until the particle size is qualified.

[0045] The present invention uses a composite ceramic powder composed of modified calcite powder, mullite powder, silicon carbide powder and boron nitride powder as a main material, a composite metal oxide composed of aluminum oxide powder, zirconium oxide powder and magnesium oxide powder as an auxiliary material, and thermoplastic plastic powder composed of polyamide powder, polycarbonate powder and polyethylene powder as a filler, and prepares high-entropy ceramic powder by means of wet ball milling and staged calcination, so that the prepared high-entropy ceramic powder has high bulk density, uniform particles, high hardness and strength, and the prepared 3D printed products have good toughness and impact strength. In addition, due to the presence of multiple elements, the 3D printed high-entropy ceramic has a higher mixing entropy, which helps to stabilize the crystal structure of the material and improve its physical properties.

[0046] The high entropy ceramic powders prepared in Example 1 and Example 2 were used for printing with a 3D printer, and the printed products were subjected to performance tests (the toughness test used the ISO 180 standard, and the impact strength test used the ASTM D256 standard), and conventional ceramic powder purchased on the market (Qiyu Technology: ADT-Al2O3-YY01-B) was used as a comparative example. The test results are shown in Table 1 below:

[0047] Table 1 Test results

[0048]

[0049] It can be seen from Table 1 above that the high entropy ceramic powder prepared in Example 1 and Example 2 of the present invention has better toughness and impact strength and excellent physical properties when compared with traditional ceramic powder materials.

[0050] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principle of the present invention should be included in the protection scope of the present invention.

Claims

1. A high entropy ceramic powder for 3D printing, characterized in that: The invention comprises the following raw materials in parts by weight: 40-50 parts of composite ceramic powder, 20-30 parts of composite metal oxide, 10-15 parts of thermoplastic plastic powder, 3-5 parts of adhesive, 5-7 parts of coupling agent and 5-10 parts of surface modifier.

2. The high entropy ceramic powder for 3D printing according to claim 1, characterized in that: The composite ceramic powder is composed of a mixture of modified calcite powder, mullite powder, silicon carbide powder and boron nitride powder, and the mixed mass ratio of the modified calcite powder, mullite powder, silicon carbide powder and boron nitride powder is 2-3:2:1:

1.

3. The high entropy ceramic powder for 3D printing according to claim 1, characterized in that: The composite metal oxide is composed of a mixture of aluminum oxide powder, zirconium oxide powder and magnesium oxide powder, and the mixing mass ratio of the aluminum oxide powder, zirconium oxide powder and magnesium oxide powder is 1-2:1:

1.

4. The high entropy ceramic powder for 3D printing according to claim 1, characterized in that: The thermoplastic plastic powder is composed of a mixture of polyamide powder, polycarbonate powder and polyethylene powder, and the mixing mass ratio of the polyamide powder, polycarbonate powder and polyethylene powder is 1-2:1:

1.

5. The high entropy ceramic powder for 3D printing according to claim 1, characterized in that: The adhesive is selected from epoxy resin powder or polyurethane powder, the coupling agent is a silane coupling agent, and the surface modifier is nano silicon dioxide.

6. The method for preparing a high entropy ceramic powder for 3D printing as claimed in claim 1, characterized in that: The following steps are involved: Step 1: Weigh 40-50 parts of composite ceramic powder, 20-30 parts of composite metal oxide, 10-15 parts of thermoplastic powder, 3-5 parts of adhesive, 5-7 parts of coupling agent and 5-10 parts of surface modifier respectively, and store them separately for future use; Step 2: ball milling the composite ceramic powder, composite metal oxide, thermoplastic powder and surface modifier by wet ball milling, adding a binder and a coupling agent to continue ball milling to obtain a ball milled mixture, and then drying the ball milled mixture; Step 3: First, the ball-milled mixture after drying is screened with a sieve, and the powder with qualified particle size obtained by screening is added into a calcining furnace for staged calcination. After calcination, it is naturally cooled to room temperature to obtain a high-entropy ceramic powder semi-finished product; Step 4: First, the high entropy ceramic powder semi-finished product is ground by a grinding machine. After the grinding is completed, the powder is evenly spread on a sieve for sieving, and the sieved powder is collected to obtain a high entropy ceramic powder finished product.

7. The method for preparing high entropy ceramic powder for 3D printing according to claim 6, characterized in that: In the step 2, the ball mill used in the wet ball milling process is selected from one of steel balls or ceramic balls, and the ball-to-material mass ratio is 1-2:1; the liquid ball milling medium used in the wet ball milling process is anhydrous ethanol; the ball milling time of the composite ceramic powder, composite metal oxide, thermoplastic plastic powder and surface modifier is 12-16 hours; the ball milling time after adding the adhesive and coupling agent is 1-2 hours; the ball mill speed is 500-900 r / min.

8. The method for preparing high entropy ceramic powder for 3D printing according to claim 6, characterized in that: In the step 2, the ball-milled mixture is placed in a drying oven and dried at a heating temperature of 60 to 80° C. for 1 to 2 hours.

9. The method for preparing high entropy ceramic powder for 3D printing according to claim 6, characterized in that: In the step three, the powder with qualified particle size obtained by screening is first calcined at a temperature environment of 300-450°C, then calcined at a temperature environment of 450-600°C, then calcined at a temperature environment of 600-850°C, then calcined at a temperature environment of 850-1000°C, and finally calcined at a temperature environment of 1000-1150°C.

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