Effect of Aging Treatment on the Mechanical Properties and Impact Abrasive Wear Property of High-Manganese Steel

High manganese steel can improve its microstructure after aging treatment, which is beneficial for enhancing strength, toughness, and wear resistance. This study aims to explore the effect of aging treatment on mechanical properties and wear resistance of high manganese steel (containing 25% Mn, called Mn25 steel) by designing different aging temperatures (450 °C, 500 °C, and 550 °C) with the same aging time (1 h). The results indicated that with the increase in aging treatment temperature, the surface hardness of Mn25 steel first increased and then decreased, but was still higher than that of untreated Mn25 steel. In addition, the impact toughness of steel decreased first and then increased with the increase in aging temperature, with the optimal hardness and impact toughness exhibited at 550 °C. The impact abrasive wear test results showed that the weight loss of Mn25 steel decreased with the increase in aging treatment temperature. After aging treatment at 550 °C, the weight loss is the lowest, which shows the optimal wear resistance performance. Under a high-impact load of 5.0 J, the hardness increased by nearly 49.96% after impact abrasive wear, and the effective hardening layer of the steel was the thickest, about 3800 μm. This is mainly related to the best match between the hardness and impact toughness of high manganese steel after aging treatment. The wear morphology is often caused by various wear mechanisms working together to cause the wear loss of Mn25 steel during the impact wear process. The wear morphologies of the Mn25 steel were mainly characterized by press-in particles, furrow, spalling, and strain fatigue. Through experimental analysis, a suitable aging treatment process has been determined, providing a theoretical basis for the practical application of high manganese steel.