Injection molding silicon carbide ceramic grinding medium and preparation method thereof

Abstract

The invention relates to the technical field of silicon carbide ceramic preparation, and particularly discloses an injection molding silicon carbide ceramic grinding medium and a preparation method thereof.The preparation method comprises the steps that 1, silicon carbide powder, a sintering aid, a binder and a solvent are subjected to ball-milling mixing and spray granulation, and silicon carbide ceramic powder is obtained; (2) adding a wax-based adhesive into the silicon carbide ceramic powder, and uniformly stirring and mixing to obtain pug; (3) performing injection molding on the pug to obtain a ceramic grinding medium particle blank; (4) performing degreasing treatment on the ceramic grinding medium particle blank to obtain a ceramic particle preform; and (5) sintering the ceramic particle preform in a vacuum sintering furnace to obtain the silicon carbide ceramic grinding medium. The prepared silicon carbide ceramic grinding medium is excellent in performance and high in wear resistance, and the service life can be greatly prolonged; the mechanical property is excellent, the normal-temperature bending strength and compressive strength are high, and the fracture resistance and the extrusion resistance are high; the density is high, the porosity is low, and the structure is compact without obvious pores.

Description

Technical Field

[0001] This application relates to the field of silicon carbide ceramic preparation technology, and more specifically, it relates to an injection-molded silicon carbide ceramic grinding media and its preparation method. Background Technology

[0002] Grinding media, as the core component for ultrafine grinding and precision milling of materials, are widely used in fields such as electronic materials, new energy batteries, and fine chemicals. Their performance directly affects grinding efficiency and finished product quality. Silicon carbide ceramics, due to their high hardness, excellent wear resistance, good chemical stability, and high thermal conductivity, have become the preferred material to replace traditional metal and alumina ceramic grinding media.

[0003] Existing methods for preparing silicon carbide ceramic grinding media mainly include dry pressing, isostatic pressing, and sol-gel methods. While dry pressing and isostatic pressing are simple processes, they are only suitable for simple spherical or cylindrical products and are difficult to prepare media with complex shapes. Furthermore, the density of the formed green body is uneven, which can easily lead to deformation and cracking during subsequent sintering, and the dimensional accuracy cannot meet the requirements of precision grinding. Although the sol-gel method can obtain high-purity green bodies, it suffers from problems such as long preparation cycle, high cost, and difficulty in large-scale production, which limits its industrial application. Injection molding technology, with its near-net-shape advantages, can accurately prepare products with complex shapes, and has high production efficiency and good dimensional consistency, making it suitable for mass production needs. However, silicon carbide powder has a large specific surface area and poor flowability. Existing injection molding processes require the addition of a large amount of binder to ensure formability, which can easily lead to binder residue and high porosity during the debinding process of the green body. At the same time, abnormal grain growth is prone to occur during the sintering stage, resulting in insufficient density and mechanical properties of the product, and the wear resistance cannot meet the stringent requirements of high-end grinding scenarios. Therefore, developing an injection-molded silicon carbide ceramic grinding media with high molding precision, excellent density, and strong wear resistance is of great industrial application value. This will solve key technical pain points in existing processes, such as binder compatibility, debinding efficiency, and sintering quality, and meet the needs of various fields for efficient and precise grinding. Summary of the Invention

[0004] To address the technical problems mentioned in the background section, this application provides an injection-molded silicon carbide ceramic grinding media and its preparation method.

[0005] A method for preparing injection-molded silicon carbide ceramic abrasive media includes the following preparation steps: (1) Silicon carbide powder, sintering aid, binder and solvent are mixed by ball milling and spray granulation to obtain silicon carbide ceramic powder; (2) Add wax-based binder to silicon carbide ceramic powder, stir and mix evenly to obtain mud; (3) The clay material is injection molded to obtain ceramic grinding media particle blanks; (4) The ceramic grinding media particle blank is degreased to obtain a ceramic particle preform; (5) The ceramic particle preform is placed in a vacuum sintering furnace for sintering treatment to obtain silicon carbide ceramic grinding media.

[0006] Preferably, in step (1), the mass ratio of silicon carbide powder, sintering aid, binder and solvent is 100:3-5:2-4:15-25.

[0007] Preferably, the sintering aid in step (1) is one of the BC-based sintering aids or oxide aid systems.

[0008] Preferably, in the BC-based sintering aid, the B content is no more than 1 wt% of the total mass of silicon carbide powder and sintering aid, and the C content is 6-10 wt% of the total mass of silicon carbide powder and sintering aid.

[0009] Preferably, the oxide additive system is a mixture of Al2O3 and rare earth oxides; the oxide additive system is composed of Al2O3 and rare earth oxides in a mass ratio of 2-4:1-1.5.

[0010] Preferably, the rare earth oxide is composed of Y2O3, CeO2 and Er2O3 in a mass ratio of 3-5:0.5-1.5:0.5-2.

[0011] Preferably, in step (1), the adhesive is composed of phenolic resin, polyquaternium-11, polyvinyl butyral and polytrimethylene carbonate in a mass ratio of 10-12:3-5:1-3:2-4.

[0012] Preferably, the solvent in step (1) is water or anhydrous ethanol.

[0013] Preferably, the mass ratio of silicon carbide ceramic powder to wax-based binder in step (2) is 100-120:10-18.

[0014] Preferably, in step (3), the injection pressure is 100-120MPa, the holding pressure is 60-80MPa, the holding time is 4-10s, the injection temperature is 160-180℃, the screw speed is 100-300rpm, and the injection speed is 50-100cm³ / s.

[0015] Preferably, the degreasing process in step (4) is as follows: first, solvent degreasing is carried out using trichloroethylene, n-heptane, or kerosene at a temperature of 40-60℃ for 6-14 hours, and then vacuum sintering degreasing is carried out at a temperature of 600-1200℃ for 12-24 hours.

[0016] Preferably, the sintering process in step (5) is performed under a vacuum of 5 × 10⁻⁶.-5 -1×10 -3 At Pa, the temperature is increased from room temperature to 600-800℃ at a heating rate of 5-10℃ / min, then increased to 1200-1500℃ at a heating rate of 10-15℃ / min, and finally increased to 1900-2000℃ at a heating rate of 3-5℃ / min. The temperature is held for 2-4 hours and then cooled to room temperature at a cooling rate of 2-10℃ / min.

[0017] An injection-molded silicon carbide ceramic abrasive media is prepared by the above method.

[0018] In summary, this application has the following beneficial effects: This application utilizes a specific ratio of Y₂O₃, CeO₂, and Er₂O₃ to form rare earth oxides, which are then combined with Al₂O₃ to form an oxide additive system. This fully activates the sintering activity of silicon carbide powder, resulting in tighter interparticle bonding, significantly increased density of the ceramic material, and a marked reduction in internal porosity. Consequently, the product exhibits superior mechanical load-bearing capacity, effectively enhancing its fracture and extrusion resistance. Furthermore, a quaternary binder system composed of phenolic resin, polyquaternium-11, polyvinyl butyral, and polytrimethylene carbonate ensures more uniform dispersion of the silicon carbide ceramic powder during mixing, more stable interparticle bonding, and better uniformity of the molded clay structure. Subsequent debinding processes result in no significant residual impurities, ultimately leading to a denser internal structure in the ceramic product and preventing uneven component distribution. This significantly improves wear resistance by addressing performance shortcomings caused by excessive heating. The degreasing process utilizes a two-step process combining solvent degreasing and vacuum sintering degreasing. This ensures the complete removal of wax-based binders from the ceramic grinding media preforms, effectively avoiding internal pores and defects caused by binder residues in single degreasing methods. This results in a purer ceramic particle preform structure, laying a solid foundation for subsequent sintering and densification. The multi-stage gradient heating vacuum sintering method allows for the gradual release of internal stress during heating, resulting in a gentler and more uniform sintering process. This effectively avoids internal cracks and structural inhomogeneities caused by excessively rapid heating, allowing the ceramic material to form a complete and dense microstructure. This further enhances its mechanical strength and wear resistance, ensuring stable and reliable overall performance during product use. Attached Figure Description

[0019] Figure 1 This is a photograph of the silicon carbide ceramic grinding media prepared in Example 1. Detailed Implementation

[0020] The present application will be further described in detail below with reference to the embodiments.

[0021] The silicon carbide powder used in the embodiments and comparative examples of this invention was purchased from Jiaozuo Shiheng Refractory Materials Co., Ltd.; Al2O3, Y2O3, CeO2 and Er2O3 were all purchased from Beijing Jinke New Materials Technology Co., Ltd.; phenolic resin (brand name: 2123) was purchased from Jinan Dahui Chemical Technology Co., Ltd.; polyquaternium-11 was purchased from Wuhan Kanos Technology Co., Ltd.; polyvinyl butyral was purchased from Shandong Guohua Chemical Co., Ltd.; polytrimethylene carbonate was purchased from Wuhan Kamik Technology Co., Ltd.; and wax-based binder (brand name: UL 00728CC) was purchased from Dongguan Xiangyi New Materials Co., Ltd.

[0022] Examples 1-3 provide an injection-molded silicon carbide ceramic grinding media and its preparation method. Example

[0023] A method for preparing injection-molded silicon carbide ceramic abrasive media includes the following preparation steps: (1) Silicon carbide powder, sintering aid, binder and anhydrous ethanol are mixed by ball milling for 12 hours in a mass ratio of 100:3:2:15 and then spray granulated to obtain silicon carbide ceramic powder. The ball milling media is 2000g of SiC balls, the ball milling ratio is 3:1, the ball milling speed is 100rpm, the inlet air temperature of spray drying is 160℃, and the outlet air temperature is 80℃. The sintering aid is composed of Al2O3 and rare earth oxides in a mass ratio of 2:1. The rare earth oxides are composed of Y2O3, CeO2 and Er2O3 in a mass ratio of 3:0.5:0.5. The binder is composed of phenolic resin, polyquaternary ammonium salt-11, polyvinyl butyral and polytrimethylene carbonate in a mass ratio of 10:3:1:2. (2) Add wax-based binder to silicon carbide ceramic powder, control the mass ratio of silicon carbide ceramic powder to wax-based binder to be 100:10, stir at 50 rpm for 2 hours, stir until uniformly mixed, and obtain mud material. (3) The clay material is injection molded, and the injection pressure is controlled at 100MPa, the holding pressure is 60MPa, the holding time is 4s, the injection temperature is 160℃, the screw speed is 100rpm, and the injection speed is 50cm³ / s to obtain ceramic grinding media particle blanks. (4) The ceramic grinding media blank is first degreased with trichloroethylene, controlling the solid-liquid mass ratio of the ceramic grinding media blank and trichloroethylene to be 1:1.5, at a temperature of 40℃ for 6 hours, and then degreased with solvent at a temperature of 600℃ and a vacuum degree of 5×10 -5 Under Pa, vacuum sintering and debinding were carried out for 12 hours to obtain ceramic particle preforms; (5) Place the ceramic particle preform into a vacuum sintering furnace and sinter it at a vacuum degree of 1×10⁻⁶. -3Under Pa conditions, the temperature was increased from room temperature to 600℃ at a heating rate of 5℃ / min, then increased to 1200℃ at a heating rate of 10℃ / min, and finally increased to 1900℃ at a heating rate of 3℃ / min. The temperature was held for 2 hours and then cooled to room temperature at a cooling rate of 2℃ / min to obtain silicon carbide ceramic grinding media. Example

[0024] A method for preparing injection-molded silicon carbide ceramic abrasive media includes the following preparation steps: (1) Silicon carbide powder, sintering aid, binder and anhydrous ethanol are mixed by ball milling for 16 hours in a mass ratio of 100:4:3:20 and then spray granulated to obtain silicon carbide ceramic powder. The ball milling media is 2000g of SiC balls, the ball milling ratio is 5:1, the ball milling speed is 150rpm, the inlet air temperature of spray drying is 190℃, and the outlet air temperature is 100℃. The sintering aid is composed of Al2O3 and rare earth oxides in a mass ratio of 3:1.2. The rare earth oxides are composed of Y2O3, CeO2 and Er2O3 in a mass ratio of 4:1:1. The binder is composed of phenolic resin, polyquaternium-11, polyvinyl butyral and polytrimethylene carbonate in a mass ratio of 11:4:2:3. (2) Add wax-based binder to silicon carbide ceramic powder, control the mass ratio of silicon carbide ceramic powder to wax-based binder to be 110:14, stir at 100 rpm for 3 hours, stir until uniformly mixed, and obtain mud material. (3) The clay material is injection molded, and the injection pressure is controlled at 110MPa, the holding pressure is 70MPa, the holding time is 7s, the injection temperature is 170℃, the screw speed is 200rpm, and the injection speed is 80cm³ / s to obtain ceramic grinding media particle blanks. (4) The ceramic grinding media particle blank is first degreased with solvent at 50°C for 10 hours using n-heptane, controlling the solid-liquid mass ratio of the ceramic grinding media particle blank and trichloroethylene to be 1:2. Then, it is degreased at 900°C under a vacuum of 1×10⁻⁶. -4 Under Pa, vacuum sintering and debinding were carried out for 18 hours to obtain ceramic particle preforms; (5) Place the ceramic particle preform into a vacuum sintering furnace, and sinter at a vacuum degree of 5×10 -5 Under Pa conditions, the temperature was increased from room temperature to 700℃ at a heating rate of 8℃ / min, then increased to 1350℃ at a heating rate of 12℃ / min, and finally increased to 1950℃ at a heating rate of 4℃ / min. The temperature was held for 3 hours and then cooled to room temperature at a cooling rate of 6℃ / min to obtain silicon carbide ceramic grinding media. Example

[0025] A method for preparing injection-molded silicon carbide ceramic abrasive media includes the following preparation steps: (1) Silicon carbide powder, sintering aid, binder and anhydrous ethanol are mixed by ball milling for 24 hours in a mass ratio of 100:5:4:25 and then spray granulated to obtain silicon carbide ceramic powder. The ball milling media is 2000g of SiC balls, the ball milling ratio is 8:1, the ball milling speed is 200rpm, the inlet air temperature of spray drying is 220℃, and the outlet air temperature is 80-120℃. The sintering aid is composed of Al2O3 and rare earth oxides in a mass ratio of 4:1.5. The rare earth oxides are composed of Y2O3, CeO2 and Er2O3 in a mass ratio of 5:1.5:2. The binder is composed of phenolic resin, polyquaternium-11, polyvinyl butyral and polytrimethylene carbonate in a mass ratio of 12:5:3:4. (2) Add wax-based binder to silicon carbide ceramic powder, control the mass ratio of silicon carbide ceramic powder to wax-based binder to be 120:18, stir at 150 rpm for 4 hours, stir until uniformly mixed, and obtain mud material. (3) The clay material is injection molded, and the injection pressure is controlled at 120MPa, the holding pressure is 80MPa, the holding time is 10s, the injection temperature is 180℃, the screw speed is 300rpm, and the injection speed is 100cm³ / s to obtain ceramic grinding media particle blanks. (4) The ceramic grinding media particle blank is first degreased with kerosene at a solid-liquid mass ratio of 1:3 to trichloroethylene at 60°C for 14 hours, and then degreased at 1200°C under a vacuum of 1×10⁻⁶. -3 Under Pa, vacuum sintering and debinding were carried out for 24 hours to obtain ceramic particle preforms; (5) Place the ceramic particle preform into a vacuum sintering furnace, and sinter at a vacuum degree of 5×10 -5 Under Pa conditions, the temperature was increased from room temperature to 800℃ at a heating rate of 10℃ / min, then increased to 1500℃ at a heating rate of 15℃ / min, and finally increased to 2000℃ at a heating rate of 5℃ / min. The temperature was held for 4 hours and then cooled to room temperature at a cooling rate of 10℃ / min to obtain silicon carbide ceramic grinding media.

[0026] Comparative Example 1 A method for preparing injection-molded silicon carbide ceramic abrasive media includes the following preparation steps: (1) Silicon carbide powder, sintering aid, binder and anhydrous ethanol are mixed by ball milling for 12 hours in a mass ratio of 100:3:2:15 and then spray granulated to obtain silicon carbide ceramic powder. The ball milling media is 2000g of SiC balls, the ball milling ratio is 3:1, the ball milling speed is 100rpm, the inlet air temperature of spray drying is 160℃, the outlet air temperature is 80℃, the sintering aid is composed of Al2O3 and rare earth oxides in a mass ratio of 2:1, the rare earth oxide is Y2O3, and the binder is composed of phenolic resin, polyquaternium-11, polyvinyl butyral and polytrimethylene carbonate in a mass ratio of 10:3:1:2. (2) Add wax-based binder to silicon carbide ceramic powder, control the mass ratio of silicon carbide ceramic powder to wax-based binder to be 100:10, stir at 50 rpm for 2 hours, stir until uniformly mixed, and obtain mud material. (3) The clay material is injection molded, and the injection pressure is controlled at 100MPa, the holding pressure is 60MPa, the holding time is 4s, the injection temperature is 160℃, the screw speed is 100rpm, and the injection speed is 50cm³ / s to obtain ceramic grinding media particle blanks. (4) The ceramic grinding media blank is first degreased with trichloroethylene, controlling the solid-liquid mass ratio of the ceramic grinding media blank and trichloroethylene to be 1:1.5, at a temperature of 40℃ for 6 hours, and then degreased with solvent at a temperature of 600℃ and a vacuum degree of 5×10 -5 Under Pa, vacuum sintering and debinding were carried out for 12 hours to obtain ceramic particle preforms; (5) Place the ceramic particle preform into a vacuum sintering furnace and sinter it at a vacuum degree of 1×10⁻⁶. -3 Under Pa conditions, the temperature was increased from room temperature to 600℃ at a heating rate of 5℃ / min, then increased to 1200℃ at a heating rate of 10℃ / min, and finally increased to 1900℃ at a heating rate of 3℃ / min. The temperature was held for 2 hours and then cooled to room temperature at a cooling rate of 2℃ / min to obtain silicon carbide ceramic grinding media.

[0027] Comparative Example 2 A method for preparing injection-molded silicon carbide ceramic abrasive media includes the following preparation steps: (1) Silicon carbide powder, sintering aid, binder and anhydrous ethanol are mixed by ball milling for 12 hours in a mass ratio of 100:3:2:15 and then spray granulated to obtain silicon carbide ceramic powder. The ball milling media is 2000g of SiC balls, the ball milling ratio is 3:1, the ball milling speed is 100rpm, the inlet air temperature of spray drying is 160℃, and the outlet air temperature is 80℃. The sintering aid is composed of Al2O3 and rare earth oxides in a mass ratio of 2:1. The rare earth oxides are composed of Y2O3, CeO2 and Er2O3 in a mass ratio of 3:0.5:0.5. The binder is composed of phenolic resin, polyvinyl butyral and polytrimethylene carbonate in a mass ratio of 10:1:2. (2) Add wax-based binder to silicon carbide ceramic powder, control the mass ratio of silicon carbide ceramic powder to wax-based binder to be 100:10, stir at 50 rpm for 2 hours, stir until uniformly mixed, and obtain mud material. (3) The clay material is injection molded, and the injection pressure is controlled at 100MPa, the holding pressure is 60MPa, the holding time is 4s, the injection temperature is 160℃, the screw speed is 100rpm, and the injection speed is 50cm³ / s to obtain ceramic grinding media particle blanks. (4) The ceramic grinding media blank is first degreased with trichloroethylene, controlling the solid-liquid mass ratio of the ceramic grinding media blank and trichloroethylene to be 1:1.5, at a temperature of 40℃ for 6 hours, and then degreased with solvent at a temperature of 600℃ and a vacuum degree of 5×10 -5 Under Pa, vacuum sintering and debinding were carried out for 12 hours to obtain ceramic particle preforms; (5) Place the ceramic particle preform into a vacuum sintering furnace and sinter it at a vacuum degree of 1×10⁻⁶. -3 Under Pa conditions, the temperature was increased from room temperature to 600℃ at a heating rate of 5℃ / min, then increased to 1200℃ at a heating rate of 10℃ / min, and finally increased to 1900℃ at a heating rate of 3℃ / min. The temperature was held for 2 hours and then cooled to room temperature at a cooling rate of 2℃ / min to obtain silicon carbide ceramic grinding media.

[0028] Comparative Example 3 A method for preparing injection-molded silicon carbide ceramic abrasive media includes the following preparation steps: (1) Silicon carbide powder, sintering aid, binder and anhydrous ethanol are mixed by ball milling for 12 hours in a mass ratio of 100:3:2:15 and then spray granulated to obtain silicon carbide ceramic powder. The ball milling media is 2000g of SiC balls, the ball milling ratio is 3:1, the ball milling speed is 100rpm, the inlet air temperature of spray drying is 160℃, and the outlet air temperature is 80℃. The sintering aid is composed of Al2O3 and rare earth oxides in a mass ratio of 2:1. The rare earth oxides are composed of Y2O3, CeO2 and Er2O3 in a mass ratio of 3:0.5:0.5. The binder is composed of phenolic resin, polyquaternium-11 and polytrimethylene carbonate in a mass ratio of 10:3:2. (2) Add wax-based binder to silicon carbide ceramic powder, control the mass ratio of silicon carbide ceramic powder to wax-based binder to be 100:10, stir at 50 rpm for 2 hours, stir until uniformly mixed, and obtain mud material. (3) The clay material is injection molded, and the injection pressure is controlled at 100MPa, the holding pressure is 60MPa, the holding time is 4s, the injection temperature is 160℃, the screw speed is 100rpm, and the injection speed is 50cm³ / s to obtain ceramic grinding media particle blanks. (4) The ceramic grinding media blank is first degreased with trichloroethylene, controlling the solid-liquid mass ratio of the ceramic grinding media blank and trichloroethylene to be 1:1.5, at a temperature of 40℃ for 6 hours, and then degreased with solvent at a temperature of 600℃ and a vacuum degree of 5×10 -5 Under Pa, vacuum sintering and debinding were carried out for 12 hours to obtain ceramic particle preforms; (5) Place the ceramic particle preform into a vacuum sintering furnace and sinter it at a vacuum degree of 1×10⁻⁶. -3 Under Pa conditions, the temperature was increased from room temperature to 600℃ at a heating rate of 5℃ / min, then increased to 1200℃ at a heating rate of 10℃ / min, and finally increased to 1900℃ at a heating rate of 3℃ / min. The temperature was held for 2 hours and then cooled to room temperature at a cooling rate of 2℃ / min to obtain silicon carbide ceramic grinding media.

[0029] Comparative Example 4 A method for preparing injection-molded silicon carbide ceramic abrasive media includes the following preparation steps: (1) Silicon carbide powder, sintering aid, binder and anhydrous ethanol are mixed by ball milling for 12 hours in a mass ratio of 100:3:2:15 and then spray granulated to obtain silicon carbide ceramic powder. The ball milling media is 2000g of SiC balls, the ball milling ratio is 3:1, the ball milling speed is 100rpm, the inlet air temperature of spray drying is 160℃, and the outlet air temperature is 80℃. The sintering aid is composed of Al2O3 and rare earth oxides in a mass ratio of 2:1. The rare earth oxides are composed of Y2O3, CeO2 and Er2O3 in a mass ratio of 3:0.5:0.5. The binder is composed of phenolic resin, polyquaternium-11 and polyvinyl butyral in a mass ratio of 10:3:1. (2) Add wax-based binder to silicon carbide ceramic powder, control the mass ratio of silicon carbide ceramic powder to wax-based binder to be 100:10, stir at 50 rpm for 2 hours, stir until uniformly mixed, and obtain mud material. (3) The clay material is injection molded, and the injection pressure is controlled at 100MPa, the holding pressure is 60MPa, the holding time is 4s, the injection temperature is 160℃, the screw speed is 100rpm, and the injection speed is 50cm³ / s to obtain ceramic grinding media particle blanks. (4) The ceramic grinding media blank is first degreased with trichloroethylene, controlling the solid-liquid mass ratio of the ceramic grinding media blank and trichloroethylene to be 1:1.5, at a temperature of 40℃ for 6 hours, and then degreased with solvent at a temperature of 600℃ and a vacuum degree of 5×10 -5 Under PaPa, vacuum sintering and debinding were carried out for 12 hours to obtain ceramic particle preforms; (5) Place the ceramic particle preform into a vacuum sintering furnace and sinter it at a vacuum degree of 1×10⁻⁶. -3 Under Pa conditions, the temperature was increased from room temperature to 600℃ at a heating rate of 5℃ / min, then increased to 1200℃ at a heating rate of 10℃ / min, and finally increased to 1900℃ at a heating rate of 3℃ / min. The temperature was held for 2 hours and then cooled to room temperature at a cooling rate of 2℃ / min to obtain silicon carbide ceramic grinding media.

[0030] Comparative Example 5 A method for preparing injection-molded silicon carbide ceramic abrasive media includes the following preparation steps: (1) Silicon carbide powder, sintering aid, binder and anhydrous ethanol are mixed by ball milling for 12 hours in a mass ratio of 100:3:2:15 and then spray granulated to obtain silicon carbide ceramic powder. The ball milling media is 2000g of SiC balls, the ball milling ratio is 3:1, the ball milling speed is 100rpm, the inlet air temperature of spray drying is 160℃, and the outlet air temperature is 80℃. The sintering aid is composed of Al2O3 and rare earth oxides in a mass ratio of 2:1. The rare earth oxides are composed of Y2O3, CeO2 and Er2O3 in a mass ratio of 3:0.5:0.5. The binder is composed of phenolic resin, polyquaternary ammonium salt-11, polyvinyl butyral and polytrimethylene carbonate in a mass ratio of 10:3:1:2. (2) Add wax-based binder to silicon carbide ceramic powder, control the mass ratio of silicon carbide ceramic powder to wax-based binder to be 100:10, stir at 50 rpm for 2 hours, stir until uniformly mixed, and obtain mud material. (3) The clay material is injection molded, and the injection pressure is controlled at 100MPa, the holding pressure is 60MPa, the holding time is 4s, the injection temperature is 160℃, the screw speed is 100rpm, and the injection speed is 50cm³ / s to obtain ceramic grinding media particle blanks. (4) The ceramic grinding media particle blank is heated at 600℃ and under a vacuum of 5×10⁻⁶. -5 Under Pa, vacuum sintering and debinding were carried out for 12 hours to obtain ceramic particle preforms; (5) Place the ceramic particle preform into a vacuum sintering furnace and sinter it at a vacuum degree of 1×10⁻⁶. -3 Under Pa conditions, the temperature was increased from room temperature to 600℃ at a heating rate of 5℃ / min, then increased to 1200℃ at a heating rate of 10℃ / min, and finally increased to 1900℃ at a heating rate of 3℃ / min. The temperature was held for 2 hours and then cooled to room temperature at a cooling rate of 2℃ / min to obtain silicon carbide ceramic grinding media.

[0031] Comparative Example 6 A method for preparing injection-molded silicon carbide ceramic abrasive media includes the following preparation steps: (1) Silicon carbide powder, sintering aid, binder and anhydrous ethanol are mixed by ball milling for 12 hours in a mass ratio of 100:3:2:15 and then spray granulated to obtain silicon carbide ceramic powder. The ball milling media is 2000g of SiC balls, the ball milling ratio is 3:1, the ball milling speed is 100rpm, the inlet air temperature of spray drying is 160℃, and the outlet air temperature is 80℃. The sintering aid is composed of Al2O3 and rare earth oxides in a mass ratio of 2:1. The rare earth oxides are composed of Y2O3, CeO2 and Er2O3 in a mass ratio of 3:0.5:0.5. The binder is composed of phenolic resin, polyquaternary ammonium salt-11, polyvinyl butyral and polytrimethylene carbonate in a mass ratio of 10:3:1:2. (2) Add wax-based binder to silicon carbide ceramic powder, control the mass ratio of silicon carbide ceramic powder to wax-based binder to be 100:10, stir at 50 rpm for 2 hours, stir until uniformly mixed, and obtain mud material. (3) The clay material is injection molded, and the injection pressure is controlled at 100MPa, the holding pressure is 60MPa, the holding time is 4s, the injection temperature is 160℃, the screw speed is 100rpm, and the injection speed is 50cm³ / s to obtain ceramic grinding media particle blanks. (4) The ceramic grinding media blank is first degreased with trichloroethylene, controlling the solid-liquid mass ratio of the ceramic grinding media blank and trichloroethylene to be 1:1.5, at a temperature of 40℃ for 6 hours, and then degreased with a vacuum of 1×10 at a temperature of 600℃. -3 Under Pa, vacuum sintering and debinding were carried out for 12 hours to obtain ceramic particle preforms; (5) Place the ceramic particle preform into a vacuum sintering furnace, and sinter at a vacuum degree of 5×10 -5 At Pa, the temperature was increased from room temperature to 1900℃ at a heating rate of 5℃ / min, held for 2 hours, and then cooled to room temperature at a cooling rate of 2℃ / min to obtain silicon carbide ceramic grinding media.

[0032] The comprehensive performance of the silicon carbide ceramic grinding media prepared in Examples 1-3 and Comparative Examples 1-6 of this application is as follows: Wear resistance: Tested in accordance with national standard GB / T 34501-2017 "Test Method for Wear Resistance of Hard Alloy". Room temperature flexural strength: Tested according to national standard GB / T 6569-2006 "Test Method for Bending Strength of Fine Ceramics"; Compressive strength: Tested according to national standard GB / T 8489-2016 "Test Method for Compressive Strength of Fine Ceramics". Density and porosity: Tested according to national standard GB / T 25995-2010 "Test Method for Density and Apparent Porosity of Fine Ceramics"; The test results are shown in Table 1.

[0033] Table 1 Performance parameters of silicon carbide ceramic grinding media prepared in Examples 1-3 and Comparative Examples 1-6

[0034] As shown in Table 1, the silicon carbide ceramic grinding media prepared in this application has excellent performance, strong wear resistance, and can significantly extend the service life; it has excellent mechanical properties, with high room temperature bending strength and compressive strength, and strong resistance to fracture and extrusion; it has high density, low porosity, and a dense structure without obvious pores, making it suitable for high-requirement grinding scenarios.

[0035] This specific embodiment is merely an explanation of this application and is not intended to limit it. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they fall within the scope of the claims of this application.

Claims

1. A method for preparing injection-molded silicon carbide ceramic abrasive media, characterized in that, The preparation steps include the following: (1) Silicon carbide powder, sintering aid, binder and solvent are mixed by ball milling and spray granulation to obtain silicon carbide ceramic powder; (2) Add wax-based binder to silicon carbide ceramic powder, stir and mix evenly to obtain mud; (3) The clay material is injection molded to obtain ceramic grinding media particle blanks; (4) The ceramic grinding media particle blank is degreased to obtain a ceramic particle preform; (5) The ceramic particle preform is placed in a vacuum sintering furnace for sintering treatment to obtain silicon carbide ceramic grinding media.

2. The method for preparing injection-molded silicon carbide ceramic grinding media according to claim 1, characterized in that, The sintering aid in step (1) is one of the BC-based sintering aids and oxide aid systems.

3. The method for preparing injection-molded silicon carbide ceramic grinding media according to claim 2, characterized in that, In the BC-based sintering aid, the B content is no more than 1 wt% of the total mass of silicon carbide powder and sintering aid, and the C content is 6-10 wt% of the total mass of silicon carbide powder and sintering aid; the oxide aid system is a mixture of Al2O3 and rare earth oxides; the oxide aid system is composed of Al2O3 and rare earth oxides in a mass ratio of 2-4:1-1.

5.

4. The method for preparing injection-molded silicon carbide ceramic grinding media according to claim 3, wherein the rare earth oxide is composed of Y2O3, CeO2 and Er2O3 in a mass ratio of 3-5:0.5-1.5:0.5-2.

5. The method for preparing injection-molded silicon carbide ceramic grinding media according to claim 1, characterized in that, In step (1), the adhesive is composed of phenolic resin, polyquaternium-11, polyvinyl butyral and polytrimethylene carbonate in a mass ratio of 10-12:3-5:1-3:2-4.

6. The method for preparing injection-molded silicon carbide ceramic grinding media according to claim 1, characterized in that, In step (2), the mass ratio of silicon carbide ceramic powder to wax-based binder is 100-120:10-18.

7. The method for preparing injection-molded silicon carbide ceramic grinding media according to claim 1, characterized in that, In step (3), the injection pressure is 100-120MPa, the holding pressure is 60-80MPa, the holding time is 4-10s, the injection temperature is 160-180℃, the screw speed is 100-300rpm, and the injection speed is 50-100cm³ / s.

8. The method for preparing injection-molded silicon carbide ceramic grinding media according to claim 1, characterized in that, The degreasing process in step (4) is as follows: first, solvent degreasing is carried out using trichloroethylene, n-heptane, or kerosene at a temperature of 40-60℃ for 6-14 hours, and then vacuum sintering degreasing is carried out at a temperature of 600-1200℃ for 12-24 hours.

9. The method for preparing injection-molded silicon carbide ceramic grinding media according to claim 1, characterized in that, The sintering process in step (5) is as follows: under a vacuum of 5×10 -5 -1×10 -3 At Pa, the temperature is increased from room temperature to 600-800℃ at a heating rate of 5-10℃ / min, then increased to 1200-1500℃ at a heating rate of 10-15℃ / min, and finally increased to 1900-2000℃ at a heating rate of 3-5℃ / min. The temperature is held for 2-4 hours and then cooled to room temperature at a cooling rate of 2-10℃ / min.

10. An injection-molded silicon carbide ceramic abrasive media prepared by the method for preparing injection-molded silicon carbide ceramic abrasive media as described in any one of claims 1-9.

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