Microstructure Limitations of High Tungsten Content Heavy Alloys

Abstract

Tungsten heavy alloys are two phase composites that are useful for several applications requiring high densities, such as radiation shields, counterbalance weights, and projectiles. This paper focuses on the density, strength and ductility variations at high tungsten concentrations (90 to 99.5 wt.% W). Fundamental relations are developed between properties, processing and micro-structure versus the tungsten content. At high tungsten levels, the strength and ductility are limited by the sintered microstructure. Furthermore, the high tungsten content heavy alloys are susceptible to impurity segregation to the tungsten-matrix interface. As a consequence, the mechanical behavior of high tungsten content alloys are sensitive to processing conditions.