Effects of Cr₃C₂ Addition on Wear Behaviour of WC-Co Based Cemented Carbides

Abstract

Microstructure, hardness, transverse rupture strength, and abrasion resistance of WC-10 wt% Co cemented carbides modified with the addition of different mass fraction of Cr3C2, in the range of 0⁻3 wt%, are studied. The influence of the microstructure, composition and hardness on the mechanical properties and wear resistance is analysed. Considering that the material under investigation can be used as die for the extrusion process of hard ceramic materials, the tribological behaviour was evaluated by performing sliding wear tests in wet conditions using a block-on-ring tribometer. Wear mechanism principally based on binder removal and subsequent fragmentation and microabrasion of the WC grains is proposed. Carbide grain size and bulk hardness can be tuned as function of specific applications by adding different amounts of Cr3C2. In particular, increasing hardness and reducing grain size by the addition of Cr3C2 are demonstrated to considerably enhance the wear performance of these carbides.

Keywords

• cemented carbides
• binder modification
• hardness
• transverse rupture strength
• wear resistance