中文摘要：

利用不同热处理方式和球化工艺,获得两种显微组织和不同硬度的等温淬火球墨铸铁（Austempered Ductile Iron,ADI）材料,利用MMS-2A微机控制摩擦磨损试验机对比研究了两种等温淬火球墨铸铁材料、车轮材料与U71Mn钢轨匹配时的滚动磨损与损伤性能.结果表明：ADI材料与U71Mn钢轨匹配时的摩擦因数明显小于车轮材料;由于ADI材料具有自润滑效果导致其磨损率明显小于车轮材料,ADI材料的自润滑性能也降低了对摩副U71Mn钢轨的磨损率,其中含有较大球状石墨和较少残余奥氏体的ADI2材料和对摩副U71Mn钢轨的磨损率最小;ADI材料的磨损机制主要表现为轻微疲劳磨损,对摩副U71Mn钢轨的磨损机制主要表现为黏着和轻微疲劳磨损,而轮轨材料匹配时的塑性流动层显著,损伤以表面疲劳裂纹和剥层损伤为主.

英文摘要：

Two kinds of austempered ductile iron （ADD with different microstructure and hardness were obtained by using different heat treatment and spheroidizing process. The rolling wear and damage properties of two kinds of ADI, wheel material and U71Mn rail were investigated using MMS-2A testing apparatus. The results show that the friction coefficient of ADI and U71Mn materials is obvi- ously lower than that of wheel material. The wear rate of ADI material is obviously smaller than that of wheel material due to a function of self-lubricating. Furthermore, the self-lubricating of ADI mate- rial decreases the wear rate of U71Mn rail material. The wear rates of ADI2 with large spherical graphite nodule dimension and less residual austenite and U71Mn rail are the smallest. The wear mechanism of ADI material is slight fatigue wear and the wear mechanism of corresponding U71Mn rail material is adhesion and slight fatigue wear. However, there is obvious plastic flow when the wheel/rail materials are applied. The surface fatigue crack and delamination damage are the main wear mechanism.