Metal injection molding (MIM) is a molding method in which a plasticized mixture of metal powder and its binder is injected into a mold. It is to first mix the selected powder with the binder, and then granulate the mixture and then inject the required shape. The polymer imparts its viscous flow characteristics to the mixture, and contributes to the uniformity of forming, cavity filling and powder filling. After forming, remove the binder, and then sinter the degreased body. Some sintered products may need further densification treatment, heat treatment or machining. The sintered product not only has the same complex shape and high precision as the product obtained by the plastic injection molding method, but also has physical, chemical and mechanical properties close to the forging. This process technology is suitable for mass production of small, precise, three-dimensionally complex metal parts and components with special performance requirements.