Alumina wear resistant ceramic firing technology

Will granular ceramic body densification and formation of solid material called sintering technology method.Sintering between particles in the body and the hollow out, will be a small amount of gas and organic impurities, between the particle growth combined with each other, to form a new substance.Burning heating device is the most widely used to use the electric stove.In addition to the normal pressure sintering i.e. pressureless sintering, hot-pressing sintering, hot isostatic pressing sintering, etc.Continuous hot-pressing sintering, although increased production, equipment and mould cost is too high, moreover due to axial heat, the length of products is limited.Hot isostatic pressing sintering with high temperature and high pressure gas pressure transmission medium, has all the advantages of uniform heat, very suitable for sintering of complicated shape products.Due to the uniform structure, material performance 30 ~ 50% higher than that of cold press sintering.10 ~ 15% higher than normal hot-pressing sintering. 

Therefore, at present, some high-value wear resistant ceramic products of alumina or national defense need special parts, such as ceramic bearing, reflector, nuclear fuel and barrel and other products, hot isostatic pressing sintering method.In addition, the microwave sintering method, arc plasma sintering process, self-propagating sintering technology is developing in the study. 

Finishing and packaging process:

 some alumina wear resistant ceramic material, after fulfilling the sintering precision work is needed.If can be used as a system of artificial bone product surface has a high degree of finish, such as a mirror, in order to increase lubricity.Due to the aluminum oxide wear-resistant ceramic materials High hardness, wear-resistant plate need more hard grinding polishing brick material for its finishing.Such as SiC, B4C or gold just drill, etc.Usually takes from coarse to fine abrasive grinding step by step, the final surface polishing.Usually can use < 1 mu m micro meters Al2O3 powder or diamond paste for grinding and polishing.In addition, the laser machining and ultrasonic grinding and cast light method can also be used.Some of the alumina ceramic parts and other materials for packaging processing.Alumina wear resistant ceramic reinforcement process in order to enhance the alumina ceramic, significantly improve the mechanical strength, new push a alumina wear-resistant ceramic reinforcement technology abroad.This novel process is simple, the technology is in the surface of alumina ceramics, using electron beam vacuum coating, vacuum sputtering coating or chemical vapor phase deposition method, plating on a layer of thin film silicon compounds, in 1200 ℃ ~ 1580 ℃ heating processing, make toughened alumina ceramics.Through enhancing the mechanical strength of alumina ceramics can be on the basis of the original increase by a wide margin, and get a degree of super-high strength aluminum oxide wear-resisting ceramics.