Preparation of ultrafine WC-10Co composite powders by reduction and carbonization

Abstract

A solid state synthesis of ultrafine/nanocrystalline WC-10Co composite powders was reported from WO₃, Co₃O₄ and carbon powders after reduction and carburization at relatively low temperatures in a short time under pure H₂ atmosphere. The effects of ball milling time and reaction temperature on the preparation of ultrafine/nanocrystalline WC-Co composite powders were studied using X-ray diffraction and scanning electron microscope (SEM). The results show that fine mixed oxide powders (WO₃, Co₃O₄ and carbon powders) can be obtained by long time ball milling. Increasing the reaction temperature can decrease the formation of Co₃W₃C and graphite phases and increase the WC crystallite size. Long-time ball milling and high reaction temperature are favorable to obtain fine and pure composite powders consisting of nanocrystalline WC from WO₃, Co₃O₄ and carbon powders.

Keywords

WC-10Co / ball milling / reduction / carburization

References

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