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injection molding
Ceramic injection molding is a new process of preparing ceramic parts developed by combining the polymer injection molding process with the ceramic preparation process.
The manufacturing process of ceramic injection molding mainly includes four links:
(1) Preparation of injection feeding: the appropriate organic carrier and ceramic powder are mixed, dried and granulated at a certain temperature to obtain the feeding materials for injection;
(2) Injection molding: the mixed injection mixture is heated and converted into sticky melt in the injection molding machine, injected into the metal mold at high speed at a certain temperature and pressure, cooled and solidified into the desired shape billet, and then demmold;
(3) Degreasing: exclude organic matter from the injected molding body through heating or other physical and chemical methods;
(4) Sintering: compact the skim ceramic billet under high temperature to obtain the required shape, appearance, size precision and microstructure.
Advantages of injection molding:
(1) Near-net molding of direct various complex geometric shapes and special requirements of small ceramic parts, so that after the sintering of the ceramic products do not need for machining or less processing, so as to reduce the expensive ceramic processing costs.
(2) High degree of mechanization and automation, short forming cycle, only for pouring, hot pressure of several tens of ten to one percent of the forming time, the strength of the billet is high, can be automated production, the management and control in the production process is also very convenient, suitable for mass production.
(3) Due to the good fluidity of the binder, the density of the injection forming blank is quite uniform.
(4) Because of the mixture of powder and binder is very uniform, the gap between the powder is very small, and the shrinkage characteristics in the sintering process are basically the same, so the density of each position is uniform, the geometric size accuracy and the surface finish are high.
Application: This technology has the most advantages for the mass production of ceramic products with high size precision and complex shape. At present, ceramic injection molding has been widely used in the molding of various ceramic powders and various engineering ceramic products. Various precision ceramic parts prepared through this process have been used in aviation, automotive, machinery, energy, optical communication, life medicine and other fields.