Dry Sliding Friction and Wear Mechanism of TiC-TiB2 Particulate Locally Reinforced Mn-Steel Matrix Composite from a Cu-Ti-B4C System via a Self-Propagating High-Temperature Synthesis (SHS) Casting Route

An Mn-steel matrix composite locally reinforced with in situ TiC-TiB2 ceramic particulates was successfully fabricated via a self-propagating high-temperature synthesis (SHS) casting route in a Cu-Ti-B4C system with various Cu contents. The effect of the Cu content on wear behavior, wear surface, and wear mechanism of the composite was investigated against an AISI H13 mating disc in similar testing conditions at various applied loads and sliding velocities. Moreover, the phase identification and microstructure of the composite were examined. With the increase in Cu content, the wear resistance of the Mn-steel matrix composite decreases first and then increases. Impressively, the composite with 30 wt% Cu content has the highest wear resistance. The enhanced wear resistance can be attributed to the combination of size of ceramic particulates, number of pores, and strength of the interfacial bonding. The dominant wear mechanisms of the TiC-TiB2 ceramic particulate-reinforced Mn-steel matrix are ploughing grooves and delamination wear associated with more abrasion and adhesion.