Distortion Prediction and Control of Injection Molded Tungsten Heavy Alloys

The distortion behavior of PIM tungsten heavy alloys was studied. The distortion mainly results from the tungsten content, lower powder loading, and the viscous flow under gravity during the full densification process. The distortion can be effectively reduced through enhanced sintering, such as, a two-step sintering process made up of solid state sintering (SSS) and liquid phase sintering(LPS), mechanical activated sintering from mechanically alloyed powder, and etc. In particular the latter, for alloys with low tungsten content, almost dense samples with good mechanical properties can be produced through solid-state sintering from the mechanically alloyed nano-composite powders, and the distortion problem related to the liquid phase can be nearly overcome completely.