Influence of size of nanoparticles and plasma pressure compaction on microstructural development and hardness of bulk tungsten samples

Bulk tungsten samples were prepared by consolidating nanosize tungsten powders using the technique of plasma pressure compaction. This innovative sintering technique offers the intrinsic capability of producing bulk samples having near theoretical density. Five different powder particle sizes, in the nanoscale, were chosen and bulk samples obtained by consolidating the powders under identical conditions of temperature, pressure and time using the technique of plasma pressure compaction. Microstructural observations and density measurement provide evidence for the presence of minimal porosity following consolidation. The influence of initial size of the powder particles on microstructural development to include the presence and distribution of porosity, density, micro-hardness, stiffness and nano-hardness is presented and discussed. (C) 2012 Published by Elsevier B.V. on behalf of The Society of Powder Technology Japan. All rights reserved.