Comparative properties of 85W-15Cu powders prepared using mixing, milling and coating techniques


Özkal B., UPADHYAYA A., Öveçoğlu M. L., GERMAN R. M.

POWDER METALLURGY, vol.53, no.3, pp.236-243, 2010 (SCI-Expanded) identifier identifier

  • Publication Type: Article / Article
  • Volume: 53 Issue: 3
  • Publication Date: 2010
  • Doi Number: 10.1179/003258909x396565
  • Journal Name: POWDER METALLURGY
  • Journal Indexes: Science Citation Index Expanded (SCI-EXPANDED), Scopus
  • Page Numbers: pp.236-243
  • Istanbul Technical University Affiliated: Yes

Abstract

Powders with a composition of 85W-15Cu (wt-%) were prepared by mixing, milling and mechanical alloying of W and Cu powders and electroless Cu coating onto W powder. Sinterability was improved by mechanical alloying and coating. The improvement due to mechanical alloying comes from a reduced particle size, assisted by activated sintering from transition element contamination in milling. Coating improved the copper dispersion, packing densities and led to a microstructure having reduced number of W-W particle contacts after compaction. Accordingly, rearrangement on liquid formation resulted in improved densification. Since copper wetting on tungsten is sensitive to oxygen contamination, coated powders ensure liquid copper dispersion throughout the compact without concern over wetting and liquid flow during liquid phase sintering.