Multimodal grain size distribution and high hardness in fine grained tungsten fabricated by spark plasma sintering

Osman El-Atwani, Dat V. Quach, Mert Efe, Patrick R. Cantwell, Bryan Heim, Bradley Schultz, Eric A. Stach, Joanna R. Groza, Jean Paul Allain

Research output: Contribution to journalArticle

Abstract

Preparation of fine grained, hard and ductile pure tungsten for future fusion reactor applications was tested using the bottom-up approach via powder consolidation by spark plasma sintering (SPS) at different temperature (1300-1800°C) and pressure (90-266MPa) conditions. Pure tungsten powders with an average particle size of about 1μm were sintered to high density (about 94%) with almost no grain growth at a temperature below 1400°C and an applied pressure up to 266MPa. These samples had a multi-modal grain size distribution (resembling the size distribution of the initial powder) and a very high Vickers hardness (up to 530kg/mm2). Above 1500°C fast grain growth occurred and resulted in a drop in hardness. XRD on the surface of bulk samples showed a small amount of tungsten oxides; however, XPS and EDS indicated that these oxides were only surface contaminants and suggested a high purity for the bulk samples. The results demonstrate that SPS can lead to ultrafine and nanocrystalline tungsten if used to consolidate pure nano tungsten powders.

Original languageEnglish (US)
Pages (from-to)5670-5677
Number of pages8
JournalMaterials Science and Engineering A
Volume528
Issue number18
DOIs
StatePublished - Jul 15 2011

Keywords

  • Grain size
  • Hardness
  • Multimodal distribution
  • Spark plasma sintering
  • Tungsten

ASJC Scopus subject areas

  • Materials Science(all)
  • Condensed Matter Physics
  • Mechanics of Materials
  • Mechanical Engineering

Fingerprint Dive into the research topics of 'Multimodal grain size distribution and high hardness in fine grained tungsten fabricated by spark plasma sintering'. Together they form a unique fingerprint.

  • Cite this

    El-Atwani, O., Quach, D. V., Efe, M., Cantwell, P. R., Heim, B., Schultz, B., Stach, E. A., Groza, J. R., & Allain, J. P. (2011). Multimodal grain size distribution and high hardness in fine grained tungsten fabricated by spark plasma sintering. Materials Science and Engineering A, 528(18), 5670-5677. https://doi.org/10.1016/j.msea.2011.04.015