MIM – Metal Injection Molding

The MIM consists of making metal components, more or less complex, by injecting a mixture of metal powder and a polymer resin thermoplastic, commonly referred to as "feedstock". This mixture is reduced to form granules and is then injected.
The binder is eliminated, debinding, which can be thermal or catalytic. This operation may require up to 24 hours.
Then, as with traditional powder metallurgy, sintering can be done either in a continuous oven in a protective environment, or in a vacuum. The MIM is in fact a process using the technique of molding plastic parts by injection with the same injection presses used for the manufacture of metal parts.
This technology is particularly well adapted to medium and large series pieces with complex geometry.

At Porite, we started manufacturing MIM parts in Taiwan in 1996. There are two types of debinding, thermal and by immersion in a solvent. High sintering temperature in a vacuum. Our main areas of activity are; tooling for power-tools, electronics, automotive, and various other fields of the mechanical industry. We inject different types of materials, iron based powders and stainless steel. Consult us.

The Process

Preparation of the feedstock >>>Injection >>>Debinding/Debonding >>>Sintering >>> secondary operations.
Secondary operations: calibration, heat treatment, surface treatment, machining, deburring.

An alternative to other technologies

The advantages of MIM

Production of complex parts
Elimination of certain machining process operations when compared to other technologies, like with lost wax casting.
Relative density of 95 to 98%
Better adhesion for anti-corrosion surface treatments when compared to traditional sintering.
Possiblity of obtaining machine-tapping or threading directly at the moment of injection
Great freedom in the geometric design of the components
Good dimensional tolerance, order of dimension + /- 0.5%