FUNCTIONALLY GRADED CEMENTED TUNGSTEN CARBIDE WITH ENGINEERED HARD SURFACE AND THE METHOD FOR MAKING THE SAME

摘要

A method for manufacturing functionally graded cemented tungsten carbide with hard and wear-resistant surface and tough core is described. The said functionally graded cemented tungsten carbide (WC-Co) has a surface layer having a reduced amount of cobalt. Such a hard surface and tough core structure is an example of functionally graded materials in which mechanical properties are optimized by the unique combination of wear-resistance and toughness. WC-Co with reduced-cobalt surface layer may be fabricated through a carburization heat treatment process following conventional liquid phase sintering. The graded WC-Co thus obtained contains no brittle ? phase.