Why does the powder injection molding process add plastic to the metal powder?
The powder injection molding process includes two parts: ceramic injection molding and metal injection molding. It is a new near-net molding technology developed by combining traditional powder metallurgy technology with plastic injection molding technology. The purpose of forming is achieved by means of injection molding, and finally powder metallurgy products are obtained by degreasing and sintering.
Organic binders play a pivotal role in the powder injection molding process, which directly affects the mixing, injection molding, degreasing and other processes in the powder injection molding process. The function of the organic binder is to bond the metal powder particles, so that the mixture has fluidity and lubricity when heated in the barrel of the injection machine, and it is the carrier that drives the powder flow. Binder selection is the key to the entire powder injection molding process, and it has a great influence on the solid filling amount in the green embryo, the green embryo strength, the deformation of the green embryo during degreasing, and the dimensional accuracy control. In the injection molding process, the mixture is heated into a plastic material with rheological properties in the barrel of the injection machine, and injected into the mold under appropriate injection pressure to form a blank. So that the product shrinks uniformly during the sintering process.
