铁路货车心盘材料的耐磨性研究

对比研究了货车心盘用ZG25MnNb钢、AAR-C级钢及经过表面强化处理的锻钢20Mn、锻钢Q345和铸钢ZG25的耐磨性能；采用金相显微镜分析了材料金相结构对其耐磨性能的影响。结果表明，对货车心盘用钢材进行表面强化能够显著改善其耐磨性能ZG25MnNb钢和经表面强化处理的锻钢20Mn的耐磨性较优；表面硬度高而组织细小的材料组成的摩擦副的耐磨性较好。

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.