Wear Resistance under Non-Lubricated Condition of Nb-Containing TWIP Steel

Abstract

ABSTRACTTwinning induced plasticity (TWIP) steels are one of the most attractive advanced high-strength steels for structural applications due to their unique combination of strength and ductility, which is associated with so-called “mechanical twinning”, where twins act as strong obstacles to the dislocation motion. In this context, Nb addition to TWIP steel increases the strength and refines grain size by nanoscale NbC precipitates. Nowadays, high-manganese TWIP steels are extensively studied. However, information in the specialized literature about their tribological properties is limited. This research work studies the wear behavior of high-manganese austenitic Fe–20Mn–1.5Si–1.5Al–0.4C TWIP steel microalloyed with Nb. The wear behavior was evaluated under non-lubricated sliding condition using the “pin-on-ring” technique. As-solution heat treated samples were worn under loads of 53, 104 and 154 N, and at sliding speeds of 0.22, 0.60 and 0.87 m/s. The wear resistance was evaluated in terms of the loss weight. Wear debris and worn surfaces were characterized by scanning electron microscopy (SEM), energy dispersive spectroscopy (SEM-EDS) and X-ray diffraction (XRD). In general, results show that the wear resistance significantly improves as the sliding speed increases. On the other hand, Nb addition to present TWIP steel produces a slight increase of the wear resistance. Also, it was found that the oxide layer plays a significant role in the wear resistance behavior of this kind of steel.