Fabrication of tungsten heavy alloy long rods by warm powder extrusion and vacuum sintering

Abstract

The long rods of tungsten heavy alloy (WHA) which contain W–5Ni–1.5Fe (wt.%) were fabricated by using warm powder extrusion. The elemental powders were first mixed, and then the mixture was prepared for warm back extrusion by adding a proper binder at 5–10 wt.% concentrations. The extrusion temperature was finely adjusted to facilitate the powder extrusion and eliminate cracks based on an extensive pre-study. Thermal debinding was also utilized prior to vacuum sintering. The results showed that the extruded rods with high length-to-diameter ratios could be obtained at the proposed binder content and extrusion temperature. The metallurgical and the mechanical characteristics of the extruded rods were evaluated and discussed with respect to the preparation route. Keywords: Tungsten heavy alloys, Warm extrusion, Thermal debinding, Vacuum sintering