Powder properties of nanocrystalline,fluidized bed reduced tungsten,tungsten carbide,and tungsten rare-earth alloy powders

摘要

Nanocrystalline materials exhibit higher strength and hardness, and changed deformation behavior, including a lack of work hardening, that provide advantages in many applications. In the hardmetal area, nanograin carbides offer unrivaled potential for strengths, hardnesses, and edge sharpness. To enable production of components and materials for applications in defense, metals processing, and the hardmetals industries, a reliable source of nano-crystalline powders is a pre-requisite. Powdermet Inc, working with the U.S. Army under the SBIR (Small Business Innovative Research) program has developed a scalable production process for converting tungsten ore concentrates and oxides directly into ultrafine and nano-scale tungsten and tungsten carbide powders using fluidized bed fast-reduction technology. Tungsten-based powders processed using fluidized bed reduction processing technology meet the needs for these mechanical and refractory applications. This powder manufacturing technology yields near-pure, sinterable tungsten and tungsten-alloy powders with surface areas exceeding 15 meters/gram, with engineered particle-size distributions of particles of less than 50 nanometer grain sizes. This paper will present powder characteristics and properties for these domestically produced tungsten based nanopowders.