MIM manufacturing process
Step 1: Blending metal powder with binder
Powder:
Metal powder that is finer than 20μm is required. Either alloy powder or pre-mixed powder may be used. Using powder finer than 20μm ensures better density for sintered parts. Relative density over 95% is usually expected.
Binder:
Plastic material is used as binder for improvement or feedstock's liquidity to facilitate injection.
Step 2: Blend and heat materials evenly
Kneading:
Blend metal powder with binder and knead while heating them to form the feedstock with metal powder evenly blended on binder base.
Step 3: Inject mold the feedstock into green parts
Injection:
Heat the feedstock to fluid which is injected into the mold to form green parts. This step is repeated several times.
Step 4: Sinter green parts in a vacuum and high heat
Vacuum sintering:
In vacuum state, heat green parts to 1100°C - 1400°C to remove binder and to compact parts. Reducing atmosphere may be used instead, although with possibly of producing inferior part density and mechanical properties.
Step 4: Step 5: Post-process the sintered parts into finished parts
