Investigation on rolling sliding wear behavior of wheel steel by laser dispersed treatment

To improve wear resistance of wheel steels under rolling-sliding wear conditions, a novel technique named laser dispersed treatment (LDT) was used by forming a regular scattered hardening pattern distributed on the surface of wheel disc, which can avoid soft zones induced by tempering effect or cracks in the overlapped region. The wear rate of LDT wheel disc was evaluated by twin-disc wear testing machine in comparison with the untreated disc. The microstructure of LDT wheel disc and untreated disc was characterized by optical microscopy (OM), X-ray diffraction (XRD) and scanning electron microscopy (SEM). This study focuses on the relationship between the of microstructure and wear resistance of laser treated zone. It is shown that a higher wear resistance of laser treated zone is attributed to the strain strengthen of retained austenite during wearing and the compressive stress within laser treated zone. The laser dispersed treatment on wheel may be a useful technique to improve the wear resistance of wheel without harmful influence on rail.