Injection molding for tough demands

Metal Injection Molding (MIM) relies on the principles applied in the unchallenged number 1 series production process for plastic components. MIM combines the advantages of injection molding and the material properties of metals.

Injection molding is the most common manufacturing technology for large-scale production of plastic parts. By mixing metal powder with a binder, the advantages of the technology can also be utilized for metal components. The binder wets the metal powder particles and permits to mold them without heating the metal to its melting point. Afterwards, the binder is removed while the metal powder is sintered and compressed.

By using various different metal powders, there is little restriction as to the choice of the specific alloy. Part weight, however, is limited to within 0.1 and 200 grams. Therefore, the process is particularly suitable for very small parts in high volumes.

The process

Powder production

The raw materials of the metal alloy are processed to powder form.

Mixing

The metal powder is mixed with the binder to feedstock.

Metering and plasticizing

The feedstock is metered into an injection molding machine, where it is plasticized by help of band heaters.

Injection

The plasticized compound is injected into the closed mold by axial forward motion of the screw.

Cooling

The part cools in the mold, thereby gaining its dimensional stability, while pressure is maintained to compensate the shrinkage of the material.

Ejection

After cooling, the mold opens and the green part is ejected.

Debinding

The binder needed for molding is removed, resulting in a porous brown part of very low strength.

Sintering

Only the sintering step gives the component its final properties. The powder particles coalesce and solidify at a temperature close to the material's melting point.

Finishing

E.g. deburring, polishing, coating, etc.

Metal powder moldings

Locking latch

  • Size: 16 x 9 mm
  • Weight: <1 g

Processor heat sink

  • Size: 46 x 46 mm
  • Weight: 46 g

Plunger

  • Size: 25 x 10 mm
  • Weight: 8 g

Auto deco weight

  • Size: 45 x 45 mm
  • Weight: 52 g

Gear shift foot lever

  • Size: 51 x 19 mm
  • Weight: 25 g
  • Material: MIM 17-4 PH

Brake foot lever

  • Size: 44 x 39 mm
  • Weight: 16 g
  • Material: MIM 17-4 PH
Benefits
  • complex geometries possible
  • tight tolerances
  • economic at high volumes

Market range

Market overview

Oesterle GmbH serves many different markets.
To give you an overview:

» Markets