Process of manufacturing an extruder screw for injection molding machines or extrusion machines and product thereof

Abstract

A process of making a composite of a sintered layer on a metal core member, such as an extruder screw having a sintered hard layer on a steel core, by charging a green compact sintering powder material into a space between an inner surface of a compressible mold and an outer surface of a mold core, sealing the compressible mold with the green compact material and the mold core therein, isostatic pressing the sealed compressible mold with the green compact material and the mold core therein, removing the mold core from the isostatically pressed green compact thus forming a cavity therein, inserting a metal core in the cavity in the isostatically pressed green compact with the metal core having a smaller transverse cross-section than the previously removed mold core and shrinking and bonding the isostatically pressed green compact onto the metal core by heating the isostatically pressed green compact and the metal core to a temperature at which the isostatically pressed green compact is sintered resulting in shrinkage thereof and bonding of the sintered material onto the metal core.

Dependencies are inferred from the claim text.