The alumina powder is prepared into powder materials according to different product requirements and different molding processes. The particle size of the powder is below 1 μm. If the high-purity alumina ceramic products are manufactured, in addition to the alumina purity of 99.99%, ultra-fine grinding and uniform particle size distribution are required. When extrusion molding or injection molding is used, a binder and a plasticizer should be introduced into the powder, generally a thermoplastic or resin with a weight ratio of 10-30%? Uniform mixing at temperature to facilitate molding operations. The powder raw material formed by the hot pressing process does not need to add a binder. If semi-automatic or fully automatic dry pressing is used, the powder has special technological requirements. It is necessary to use the spray granulation method to process the powder to make it appear spherical, so as to improve the fluidity of the powder and facilitate automatic filling of the mold during molding. wall. In addition, in order to reduce the friction between the powder and the die wall, it is necessary to add 1-2% lubricant, such as stearic acid, and the binder PVA. At present, Zhongming Ceramics has a complete set of alumina ceramic production lines, a complete processing line from mold design, injection molding, and precision machining.

For dry pressing, the powder needs to be spray granulated, and polyvinyl alcohol is introduced into it as a binder. Water-soluble paraffin is used as a binder for Al2O3 spray granulation, and has good fluidity under heating. The powder after spray granulation must have good fluidity, loose density, and the flow angle friction temperature is less than 30 ℃. The particle gradation ratio is ideal and other conditions to obtain a larger green density. Forming methods of alumina ceramic products include dry pressing, grouting, extrusion, cold isostatic pressing, injection, casting, hot pressing and hot isostatic pressing. In recent years, pressure filtration molding, direct solidification injection molding, gel injection molding, centrifugal grouting and solid free molding have been developed at home and abroad in recent years. Products with different product shapes, sizes, complex shapes and precision require different molding methods.