To obtain an alumina ceramic material with high wear resistance, it is not only necessary to consider its high density, high flexural strength and compressive strength, but also to improve its hardness and fracture toughness, which are very different from alumina ceramics. The microstructure (closed porosity, grain size, glass phase distribution, etc.) and its wear mechanism are closely related.

1. Influence of raw material powder The most important raw material of alumina wear-resistant ceramics is high-purity alumina powder. Its properties and content have a great influence on alumina wear-resistant ceramics. Ceramic powder will inevitably introduce impurities during the preparation process, and organic impurities will be bued during the sintering process, and irregular pores will be formed during the densification process; inorganic impurities will react with the ceramic powder at high temperatures or in the matrix. microcracks are formed. These impurities have a significant effect on the densification of alumina ceramics. The particle size of the raw material powder also has a great influence on the performance of the product. Only when the raw material is fine enough, the final sintered product can form a microcrystalline structure, which makes it have good wear resistance. Therefore, high-purity, fine-grained alumina powder is an important prerequisite for the preparation of wear-resistant alumina ceramics.

Influence of molding method Production practice and a large number of studies have shown that alumina ceramics with low porosity and high density have excellent structural properties. High density refers to the close arrangement of grains in the ceramic body, which is not easy to develop and form destructive breakthrough points when subjected to exteal environmental loads or corrosive substances. In order to obtain a high density ceramic body molding method is crucial. Alumina wear-resistant ceramics can generally be formed by dry pressing, wholesale china alumina ceramic components  isostatic pressing, and hot die casting. Different sintering methods have different characteristics and have different effects on the sintering properties and microstructure of alumina ceramics. Products with complex shapes are generally made by grouting or hot-press casting, and products with simple shapes are formed by dry pressing.

3. Sintering effect Sintering is a key stage of ceramic preparation, and the sintering atmosphere has a great influence on the preparation of ceramic materials. Too high sintering temperature or too long holding time will promote the growth of crystals, so that fine raw materials will develop into coarse grains at high temperature, and the content of liquid phase will increase. This not only reduces strength, but also wear resistance. Of course, if the temperature is too low, the sintered body is not dense, and the wear resistance of the product is not good. High-quality electric sintering fuace sintering can precisely control the heating, holding and cooling process, and has an important role in improving the wear resistance of ceramics, but the sintering cost and refractory consumption of electric kilns are higher than coal mines. 4. Combustion accelerant The suitable sintering agent reduces the temperature during the sintering process, improves the microstructure of the ceramic, and improves the mechanical properties, thereby effectively improving the wear resistance of the alumina wear-resistant ceramic.

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