| 摘要 |
In order to provide cemented carbide, provision is made about tungsten carbide powder which has a grain size not smaller than 1 mu m and which is mixed with carbon powder and chromium powder to form raw powder. The tungsten carbide powder is formed by fine primary crystal particles of tungsten carbide and satisfies an inequality given by: Y>0.61-0.33 log (X), where Y denotes a half-value width of (211) crystal planes in tungsten carbide (JCPDS-card 25-1047, d=0.9020) measured by a X-ray diffraction method and where X denotes a grain size measured by the FSSS method. There is also provided a method of producing the composite carbide powder having tungsten carbide powder as a main element, the method comprising the steps of preparing tungsten powder which has a mean grain size not smaller than 1 mu m, mixing the tungsten powder with carbon powder and chromium powder into a mixture, and processing the mixture in a predetermined atmosphere into fine primary crystal particles of tungsten carbide. One or more of the following additional components may be added to the mixture: Ta, Mo, Nb and Zr.
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