Wear modes in open porosity titanium matrix composites with TiC addition processed by spark plasma sintering

Abstract

Abstract This work focused on the influence of TiC reinforcing particles on the tribological properties of titanium matrix composites (TMCs) with open porosity, processed by spark plasma sintering (SPS). Materials composed of an equimolar mixture of Ti and TiH2 with 0, 3, 10 and 30 vol.% of TiC were sintered at 850 °C. Nanoindentation and wear tests were carried out to assess the nanohardness and the wear resistance in a tribometer with a reciprocating sliding ball-on-flat configuration. Results showed a nanohardness increment from 5 to 14 GPa with increasing TiC content. The coefficient of friction (CoF) showed a minimum of 0.2 for 10% TiC grade, which also showed the lowest wear rate. For the low TiC content sample, adhesive wear with severe plastic deformation was identified. Meanwhile, medium content TiC sample showed a mechanical mixed layer (MML), whereas high TiC content composite showed abrasive as the main wear mechanism. In conclusion, the wear mechanisms, CoFs and wear volume changed with TiC content.