Wear Resistance of Materials for Lining Seat of Freight Vehicle

The wear resistance of ZG25MnNb, AAR grade C steel, 20Mn, Q345, and ZG25 steel was comparatively investigated. The effect of surface hardening on the hardness and wear resistance of the steels was examined, while the correlation among the microstructures and wear resistance of the steel was discussed. Thus an MM-200 friction and wear tester was performed to evaluate the wear resistance of various steels pairing with surface hardened forged 20Mn steel. The hardness of the steel samples was determined, while the surface and cross-section microstructures of the steels were observed on a scanning electron microscope. It was found that surface hardening contributed to significantly improving the wear resistance of the steels, which was dependent on the increase of the hardness and decrease of the grain sizes caused by the surface hardening. The surface hardened forged 20Mn self-mated pair showed much better wear resistance than the other pairs and was applicable to prepare the lining seat of freight vehicle. Since the surface modification had great effects on the hardness and grain size of the steels, which in turn had a great effect on the wear resistance, it was therefore suggested to pay enhanced attention on the optimization of the surface modification process in developing novel steels suitable to the freight vehicle lining seat.