MIM metal injection molding is a molding method for injection molding of metal powder and binder in the model. It is the first choice of powder and binder are mixed, then the mixture was injected to granulation forming shape. The characteristics of the viscous flow of the polymer can be given to the mixture, which is helpful to the uniformity of forming, cavity filling and powder filling. After the forming process, the binder is excluded, and then the sintered compact is sintered. Some sintering products may also be further densification treatment, heat treatment or machining. Sintered products not only have the same complex shape and high precision as the plastic injection molding method, but also have physical, chemical and mechanical properties close to the forging process. The technology is suitable for large scale production of small, precision, three-dimensional shape complex, as well as the production of metal parts with special performance requirements.