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Cerium enrichment on sinter skin of mischmetal doped WC-Co cemented carbide

  • Zhang Li Email author
  • Chen Shu 
  • Xiong Xiang-jun 
  • Huang Bai-yun 
  • Zhang Chuan-fu 
Materials Science and Engineering

Abstract

Rare earth-doped WC-Co cemented carbides with low carbon-containing level were prepared by adding mischmetal (mainly containing lanthanum and cerium) in the form of cobalt pre-alloyed powder during ball-milling. After sintering, the sinter skin (exterior) was observed and analyzed by scanning electron microscopy (SEM) and energy disperse X-ray spectroscopy (EDXS). The results show that during the sintering process lanthanum and cerium are separated and cerium predominantly migrates towards the surface forming precipitates containing oxygen. Thermodynamic analysis and polarization of cerium atom caused by the strong interaction between cerium atoms and high energy carbon atoms were used in explaining the observed phenomenon.

Key words

hardmetal lanthanum cerium atom polarization thermoldynamics enrichment 

CLC number

TF125.3 TF124.5 

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Copyright information

© Central South University 2005

Authors and Affiliations

  • Zhang Li 
    • 1
    Email author
  • Chen Shu 
    • 2
  • Xiong Xiang-jun 
    • 1
  • Huang Bai-yun 
    • 1
  • Zhang Chuan-fu 
    • 3
  1. 1.State Key Laboratory of Powder MetallurgyCentral South UniversityChangshaChina
  2. 2.Changsha Mining and Metallurgy Research InstituteChangshaChina
  3. 3.School of Metallurgical Science and EngineeringCentral South UniversityChangshaChina

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