Microscale experimental and modeling wear studies of rail steels

Rail steel with bainite microstructure was developed to further increase steel hardness for improved durability and wear. Even though bainitic steel has higher bulk hardness, it showed worse wear performance than pearlitic steel, which was attributed to the superior work hardening capabilities of conventional pearlitic steel under severe operating stress conditions. As the effects from the wheel/rail contact are confined to the topmost surface and sub-surface layers, convenient and well-instrumented wear experiments at the microscale were performed and compared with model results. Specifically, a finite element model was developed to simulate microscale wear, including repeated sliding contact to investigate tangential plastic strain. It was found that a simple scratch wear technique along with a computational model could investigate rail wear as well as used as a design tool in developing new rail steels.