FUNCTIONALLY GRADED WC/CO/DIAMOND COMPOSITES

摘要

Laminated composites of WC/Co/Diamond, wherein a WC/Co substrate provides mechanical support for a diamond facing, are established rock cutter materials. However, the laminated material is susceptible to de-cohesion at the substrate-diamond interface, and wear dramatically increases once the diamond facing is breached. A potential solution to this problem is to develop a functionally graded interface between the diamond facing and its supporting WC/Co substrate. In this paper, such a structure has been produced by carbon infiltration of a sponge-like WC/Co nanocomposite with fullerene soot, followed by high pressure sintering and transformation of the fullerene-derived carbon to diamond. The cutting properties of natural diamond, 2-D laminates and 3-D composites, against a granite block and Al-Si log, were compared. The functionally graded material displayed higher wear resistance.