Journal of Central South University of Technology

, Volume 13, Issue 6, pp 603–607 | Cite as

Phase transformation of nano-grained W(Co, C) composite powder and its phase constitute

  • Cao Shun-hua  (曹顺华)Email author
  • Cai Zhi-yong  (蔡志勇)
  • Zhou Jian-hua  (周建华)
  • Li Jiong-yi  (李炯义)
  • Lin Xin-ping  (林信平)


A new process of WC-Co cemented carbide was developed by using nano-grained W(Co, C) composite powders as raw materials processed by high-energy ball milling. X-ray diffraction(XRD), differential thermal analysis (DTA), thermo-gravimetric (TG) analysis and coercive forces of the sintered samples were adopted to analyze the phase transformation and constitution, and the microstructures of sintered samples were characterized by scanning electron microscopy(SEM). The results show that the as-milled powders are transformed into transitional phases W2C and η (Co3W3C or Co6W6C) during sintering, and finally transformed into WC and Co phases completely at 1 250 °C for 30 min, and a large number of fibrous WC grains with about 1.2 μm in length and 100 nm in radial dimension are formed in the sintered body at 1 300 °C.

Key words

cemented carbide phase transformation high-energy ball milling fibrous WC grain 

CLC number



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Copyright information

© Published by: Central South University Press, Sole distributor outside Mainland China: Springer 2006

Authors and Affiliations

  • Cao Shun-hua  (曹顺华)
    • 1
    Email author
  • Cai Zhi-yong  (蔡志勇)
    • 1
  • Zhou Jian-hua  (周建华)
    • 1
  • Li Jiong-yi  (李炯义)
    • 1
  • Lin Xin-ping  (林信平)
    • 1
  1. 1.State Key Laboratory of Powder MetallurgyCentral South UniversityChangshaChina

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