Le moulage par injection de poudres métalliques

Obtention de pièces a haute densité relative et aux cotes finales

Plastics technology - A plus for powder metallurgy

Net-shape, high density P/M parts by injection molding

¹ My-Hanh Technology Inc., Oakland, Californie, Etats-Unis.
² Société française de métallurgie, Paris.

Abstract

The major attraction of injection molding is its relative freedom to shape parts with intricate geometries. In the USA, companies are actively producing or experimenting with metal or ceramic injection molding, closely followed by their European and Japanese counterparts. All injection molding technics comprise three basic steps :

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  finding suitable metal powders, mostly micron-size and with high packing density,

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  mixing with an organic binder and molding green parts,

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  extracting the binder and sintering for low porosity, with the exception of parts which are unmoldable or which can be made satisfactorily by conventional P/M, or for which injection molding is the only viable method, each case needs an individual cost analysis by comparison with traditional forming technics.

Applications include high temperature structural ceramics, mechanical components for high cycle fatigue service, biomedical implants, parts in stainless steels, refractory metals, cemented carbides, electronic and magnetic materials.