Removal of Ni-Activator from the Activated Sintered W-Compact by High Vacuum Treatment

  • In-Hyung Moon
  • Yuong-Hwan Kim
  • Myung-Jin Suk

Abstract

A small amount of nickel added to W-powder as an activator can increase greatly the sinterability of the W-powder compact, enabling full densification to be achieved at the relatively low sintering temperature of about 1200ºC–1400ºC. However, the presence of Ni-activator causes a negative effect on the mechanical properties of the activatedly sintered W-parts, resulting in extreme brittleness associated with a brittle Ni-rich phase. Therefore, Ni-activated sintered W-compacts can not be subjected to further plastic working process for a final shaping.1 If after playing a positive role as an activator in the first stage of sintering,the Ni-activator can be removed fully or partly from the activated sintered W-compact, the degree of detrimental effect might be substantially reduced.

Keywords

Evaporation Rate Initial Porosity Reference Specimen Weight Loss Rate Sintered Compact 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1989

Authors and Affiliations

  • In-Hyung Moon
    • 1
  • Yuong-Hwan Kim
    • 1
  • Myung-Jin Suk
    • 1
  1. 1.Department of Materials EngineeringHan Yang UniversitySeoulKorea

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