Alumina ceramics have high mechanical strength, high hardness, wear resistance, corrosion resistance, and high temperature. They are widely used in many fields such as chemical industry, construction, electronics and so on. According to the different content of alumina in ceramics and their uses, they are divided into many types. This article focuses on 99% alumina ceramics. The main raw material of 99% alumina ceramics is 99% alumina. Therefore, 99% alumina used to study the characteristics of 99% alumina ceramics is composed of α-Al2O3. The temperature change range of its bending strength is small and the fracture toughness is old. The drop in temperature gradually rises, and the thermal conductivity of 99% alumina at low temperatures is much lower than that of stainless steel. Therefore, if alumina ceramics is used instead of stainless steel as the superconducting insulating support material, the heat leakage of the system can be greatly reduced, and the alumina ceramics can improve the stability of the superconducting magnet.
alumina ceramic structural parts
99% alumina ceramics can be used in the manufacture of 99% alumina ceramic substrates. The substrates made with it have smooth surface, no defects, uniform composition, high strength, high flexibility, easy to cut and process, and are widely used in industrial production. In addition, it can also be used to make special wear-resistant materials such as high-temperature crucibles, refractory furnace tubes, ceramic bearings, and ceramic seals.
Hot-pressing sintering process, that is, heating the green body while pressing, sintering can not only be achieved by diffusion and transfer of substances, plastic flow plays an important role, the sintering temperature of the green body is much lower than that of atmospheric sintering, the current hot-pressing sintering The method is the pressure sintering method and the (HIP) method, which can apply isotropic pressure to the green body, and the fine structure of alumina ceramics is more uniform than that of the pressure sintering method.
The hot-pressing sintering technology is especially suitable for the sintering of transparent alumina ceramics and microcrystalline corundum ceramics. Alumina ceramics can well inhibit the growth of crystal grains. Alumina ceramics can obtain dense microcrystalline high-strength alumina ceramics. In addition, alumina sintering The process is the diffusion of anions. Therefore, vacuum sintering and hydrogen atmosphere sintering are effective auxiliary means to achieve low-temperature sintering of alumina ceramics.
