The shape of the grinding medium ball is mainly produced by pressing the embryo body through its high temperature during the process of production. The embryo body is mainly made of particle-pressed alumina grinding balls, so the sintering of the ceramic Not only is the sintering behavior between the particles, but more important is the sintering behavior of the body. Sintering is an important part of ceramic firing. There are many factors that affect the sintering of the green body, and the inherent factor is the characteristics of the powder.
The powder properties of the grinding medium ball are an important factor influencing the sintering to a certain extent. The surface energy is one of the driving forces of the particle sintering during the operation. The morphology has a great influence on the surface energy of the particles, so the particle morphology of the ceramic The effect of sintering is considerable. Rough surface particles have a relatively large specific surface area or surface energy, so the sintering driving force is large, easy to sinter, the sintering density is large, and the holes are small and small.
The surface smooth granular particles of the grinding media ball have a relatively small specific surface area or surface energy during the operation, so the sintering driving force is small, and it is not easy to sinter during operation, and the sintered density of the ceramic is relatively low. Big and many. Compared with granular particles, plate-like particles have a large specific surface area, a large driving force for sintering, and are easy to sinter. The sintering density of ceramics is larger. Compared to a green body composed of small hard agglomerates and non-agglomerates, the porosity is large, the density of green bodies is small, the density of ceramics is also small, and the sintered density of ceramics is low.
When the grinding medium ball is in operation, when its grains are fine, its wear mechanism mainly occurs plastic deformation and partial transgranular fracture, so that it can produce slight wear to a certain extent, and when the grains are coarse, the wear mechanism is The grain boundary fracture occurs mainly, and the wear is severe. Therefore, the smaller the grain size is, the better the wear resistance of the ceramic is. Therefore, it should be possible to use a small particle size of aluminum oxide raw materials in order to reduce the ceramic grain size. In addition, compared with large particles, small particles have a relatively large specific surface area or surface energy, so the sintering driving force is large, the sintering temperature is low, and the sintering density is high.
The sintering aid of the grinding media ball helps to reduce the sintering temperature during the operation, so that the microstructure of the ceramic can be effectively improved, the mechanical properties can be improved, and the wear resistance of the ceramic ball can be improved. The quality of sintering aids includes quantity, phase composition, chemical composition and fineness. The calcining agent is generally formulated using a SiO2-CaO-MgO ternary system. Should avoid the use of high-temperature gas evolution and phase change of sintering aids, so as to avoid new defects, and affect the product densification and pass rate, reduce product competitiveness.