The damage and crack propagation mechanisms in railway wheels have been extensively studied and described,, for instance in [1,2]. Thermo-mechanical coupled loads, [3-5], and manufacturing process defects effect on fatigue life, [6,7], have been also deeply investigated. In the wheel design against fatigue, knowledge of material cyclic properties is essential. Experimental data are derived from mechanical tests on samples directly machined from wheels, taking into account the eventual anisotropic characteristics of wheels, due to the forging process at production and to the rolling contact in operation, [2]. In this paper the cyclic plastic response in the domain of low plastic strain amplitudes, and the fatigue properties of a ferritic-pearlitic railway wheel steel, are presented and discussed. Cyclic curves at different stress levels and S-N curve in high-cycle fatigue (HCF) regime were obtained from constant stress amplitude tests.
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