1. Technical concept

Metal injection molding (MIM) combines plastic injection molding with metal powder fusion. A fine metal powder is mixed with a binder and injected into a mold—when the part is finished the binder is removed, leaving a metal part or structure that is then sintered into its final form.

MIM is often selected for small, complex parts with unique geometries that cannot be efficiently manufactured using other manufacturing methods—for example, medical devices and components.

2.Metal Injection Molding Process

Step 1: Feedstock – Very fine metal powders are combined with thermoplastic and wax binders in a precise recipe. A proprietary compounding process creates a homogenous pelletized feedstock that can be injection molded just like plastic. This achieves ultra-high density and close tolerances over high-production runs.

Step 2:  Molding – The feedstock is heated and injected into a mold cavity under high pressure, allowing for extremely complex shapes. Once the component is removed it is known as a "green part."

Step 3: Debinding – the “green part” is then put through a controlled process called debinding that removes the binder and prepares the part for the final step. Once the debinding is complete, the component is referred to as “brown.”

Step 4: Sintering – the “brown” part is held together by a small amount of binder and is still fragile. During sintering temperatures reach near the melting point of the material. Sintering eliminates the remaining binder and gives the part its final density and strength.