Journal of Inorganic Materials ›› 2017, Vol. 32 ›› Issue (8): 813-818.doi: 10.15541/jim20160590

• Orginal Article • Previous Articles     Next Articles

Grain Growth Inhibitor on the WC-Co Cemented Carbide Coating

Xue-Zheng WANG(), Hai-Bin WANG, Xue-Mei LIU, Tao YANG, Xiao-Yan SONG()   

  1. College of Materials Science and Engineering, Key Laboratory of Advanced Functional Materials, Education Ministry of China, Beijing University of Technology, Beijing 100124, China
  • Received:2016-10-28 Revised:2016-11-25 Online:2017-08-10 Published:2017-07-19
  • About author:WANG Xue-Zheng. E-mail: w2003-2008@163.com
  • Supported by:
    863 Prograns (2013AA032001);Natural Science Foundation of Beijing (2131001, 2154045)

Abstract:

The ultrafine WC-12Co composite powder was synthesized by in situ reduction and carbonization reactions. Using the composite powder with an addition of 1.0wt% grain growth inhibitor (GGI) i.e. VC, Cr3C2 and NbC, as raw materials, the ultrafine-structured cemented carbide coatings were fabricated by the high velocity oxy-fuel (HVOF) spraying method. Prior to thermal spraying, the powders were agglomerated into thermal spray feedstock. The effects of GGI addition on phase constitution, microstructure, hardness, and wear and corrosion properties of the coatings were investigated. The results show that the mean WC particle size of coatings with an addition of 1.0wt% VC or Cr3C2 decreases by about 49% as compared to that without GGI. Moreover, hardness of the coatings is significantly improved and the wear rate decreases by 52%-55%. Addition of 1.0wt% NbC has little effect on WC particle size of the coating but leads to formation of (W, Nb)C compound in the Co binder. Thus the corrosion resistance of the coating containing NbC is significantly enhanced. However, its wear resistance is lower than those with VC or Cr3C2, due to high brittleness of the (W, Nb)C compound.

Key words: grain growth inhibitor, ultrafine WC-Co composite powder, cemented carbide coating, wear resistance, corrosion resistance

CLC Number: 

  • TQ174