A Study of Reduced and Carburized Reactions in Dry-Milled WO₃+Co₃O₄+C Mixed Powders with Different Carbon Content

Abstract:

The dry-milling technique was used for mixing and crushing oxides and graphite powder to get homogeneous mixed powders. The weight ratio of ball-to-powder was 30:1 and argon gas was filled in jar. The carbon content was more 10~ 20wt% than the stoichiometric amount. The drymilling was carried for 20 hours. After milling, the mixed powders were reduced and carburized at 900~980°C for 3 hours flowing Ar gas in tube furnace. The dry-milled powders showed wide diffraction patterns of X-ray. The reactions of reduction and carburization were completed in 3 hours at 980°C. After the reactions, the mean size of WC particles was about 200 nm. The content of free carbon in WC/Co mixed powders decreased as the reaction temperature increased.

• Periodical: Materials Science Forum (Volumes 534-536)
• Pages: 1149-1152
• DOI: https://doi.org/10.4028/www.scientific.net/MSF.534-536.1149
• Online since: January 2007
• Authors: Hoo Soon Im, Jah Mahn Hur, Wan Jae Lee
• Keywords: Carbon Content, Carburization, Cemented Carbide, Nanosized WC, Reduction, WC/Co Composite Powder

References

[1] S.I. Cha, S.H. Hong, G.H. Ha, B.K. Kim: Scripta Materialia Vol. 44 (2001), p.1039.

[2] G. Gille, J. Bredthauer, B. Gries, B. Mende, W. Heinrich: Int. J. of Refractory Metal & Hard Materials Vol. 18 (2000), p.87.

DOI: 10.1016/s0263-4368(00)00002-0

[3] J. Gurland: Trans. AIME., Feb. (1954), p.285.

[4] H. E. Exner, J. Gurland: Powder Metal. Vol. 25 (1970), p.13.

[5] V. Adelskold, A. Sundelin, A. Westgren, Ztsch. Allogen. Chem. (1933), p.212.

[6] Nishiyama, Ishida: J. of Sumitomodenki Vol. 7 (1958), p.26.