On Mechanical Properties of New Railway Wheel Steels for Desert Environments and Sand Caused Wheel Damage Mechanisms

Worn railway wheels after service in the desert were investigated by means of failure analysis, hardness measurements, tensile tests, fracture toughness tests and low-cycle fatigue (LCF) tests. The results complete both previous small-scale laboratory experiments and FEM simulations performed by the authors on widely used steels and new steel grades allowing to better understand the main damage mechanisms due to the sand. These new steel grades were developed for forged-rolled solid wheels in alternative to AAR Class B/C/D steel grades and were designed to ensure high resistance to wear and rolling contact fatigue in the presence of sand, debris or gravel on the rails. This paper covers the in-depth mechanical characterization of wheels made of the new steels. Hardness measurements, tensile tests, fracture toughness tests and LCF tests were carried out. The results are compared with AAR Class B/C/D steels showing an excellent combination of fracture toughness, cyclic yield strength and ductility.