Novel ultra-coarse hardmetal grades with reinforced binder for mining and construction

Abstract Novel ultra-coarse WC–Co grades with a Co-based binder reinforced with nano-particles have been developed and implemented in industry on a large scale. The new grades with the brand name MASTER GRADES®, consist of rounded WC grains and the Co-based binder comprising nano-particles of the θ-phase (Co2W4C). The new hardmetal grades are characterised by a combination of higher hardness and transverse rupture strength as result of the binder hardening and reinforcement. Wear-resistance of the new grades in laboratory tests on abrasion, cutting of granite and abrasive concrete is found to be 2–3 times higher than that of standard grades with the same Co content and similar WC mean grain size. Life of mining and construction tools with the MASTER GRADES® is dramatically prolonged as a result of their enhanced wear-resistance and resistance to the initiation and propagation of thermal and fatigue cracks.