Production Technology Of Alumina Industrial Ceramics
Production Technology Of Alumina Industrial Ceramics
Alumina industrial ceramics material has been seen a lot, this kind of industrial ceramic material application of alumina chemical properties, but not alumina and ceramic combination, this kind of alumina ceramic material and other different materials with the same route, thermal conductivity and ductility have a great advantage.Alumina is also the chemical name of aluminum oxide (Al2O3), while the chemical composition of ceramics are usually silicon dioxide (SiO2) and calcium carbonate (CaCO3).The finishing process of alumina ceramics is powder preparation, this preparation method has high molding rate, fast working efficiency and high success rate of products.
The finishing process of alumina industrial ceramics is to prepare the aluminum oxide powder into powder materials by different forming processes according to different product requirements.This powder particle size requirements in 1μm below, if the manufacture of high purity alumina industrial ceramics parts or industrial ceramic structural products, then in addition to alumina purity to 99.99%, but also need to powder ultrafine grinding and has been ultrafine powder particle size distribution uniform.Then the powder has been crushed by extrusion molding or injection molding method, in the preparation process of powder need to introduce binder and plasticizer, it should be noted that binder and plasticizer have a certain proportion of requirements.
In general, thermoplastics or resins with a weight ratio of 10-30%.The organic binder should be evenly mixed with the alumina powder at a temperature of 150-200 degrees Celsius to facilitate the molding operation.If the hot pressing process is used, the powder raw material does not need to add binder.
If the method is semi-automatic or automatic dry pressing molding, the powder has a special process requirements, which requires the use of spray granulation method to treat the powder.The alumina precision ceramic products appear to be spherical, which is also conducive to improve the fluidity of the powder and facilitate the automatic filling of the die wall in the process of the powder material forming.In addition, in order to reduce the friction between the powder and the mold wall, it is necessary to add 1 ~ 2% lubricant, such as stearic acid, and binder PVA, etc.
