A comparative study of two high performance railway wheel steels

An experimental and numerical investigation was carried out in order to characterize and compare the response to cyclic loading of two railway wheel steels: the ER8 EN13262 and the SUPERLOS®. Cyclic contact tests were carried out by a two disc testing machine on the wheel steels samples coupled with UIC 900A rail steel samples. All couples were subjected to the same contact pressure, rolling speed and sliding/rolling ratio, with varying lubrication condition. Wear and friction were monitored during the tests; at the end of the tests, analyses of the subsurface microstructure and hardness profiles were carried out. Numerical simulations aimed at characterizing the material response to cyclic loading were carried out; in particular, cyclic plasticity, wear and subsurface origin fatigue models were calibrated. An example of application to real wheels assessment was provided.