Copper–nickel-based diamond cutting tools: stone cutting evaluation

The current trend to replace cobalt in diamond cutting tools (DCTs) for stone cutting has motivated the study of alternative materials for this end. The present study evaluated the performance of several diamond-reinforced copper–nickel composites as regard to their suitability for serving as stone cutting materials. Cobalt (Co) and copper–nickel composites (Cu–Ni; Cu–Ni–10Sn, Cu–Ni–15Sn, Cu–Ni–Sn–2WC, and Cu–Ni–Sn–10WC) reinforced with 4 wt% of diamond particles were produced by hot pressing, at a temperature of 850 °C during 15 min and under an applied pressure of 50 MPa. The obtained specimens were characterized in terms of Vickers hardness and shear strength. The microstructure was analyzed by the means of SEM/EDS. A pin-on-disc wear test, with the composite serving as pin and a stone serving as disc, was performed in order to assess the tribological properties and cutting performance. Cu–Ni–Sn–10WC showed to be the material with the best cutting properties, with the highest disc/pin wear ratio registered among the remaining competing materials. This material arises as a promising alternative to be used in the stone cutting industry.