In the last decades a large number of researchers investigated the different failure mechanisms of railroad rails, including wear and surface or subsurface initiated RCF (rolling contact fatigue); due to the continuous increase of in service conditions severity, failure occurrence is increasing not only for rails but also for wheels. The behaviour of R7T wheel steel under rolling contact fatigue conditions has been investigated in the present paper, by means of a twin disc Amsler machine; tests were performed under dry or water lubrication conditions, different contact loads and slide/roll ratio gamma. Both cylindrical and convex rollers have been used to assess the influence of the stress distribution under the contact area. Test results made evident the negative effect of small slide/roll ratio values and the crucial role played by water lubrication in accelerating crack nucleation and propagation. Scanning electron microscope analysis of longitudinal cross sections of the rollers allowed to investigate the typical RCF failure mechanisms and the morphology of propagating cracks. (VDEh)
Rolling contact fatigue in R7T rail wheel steel
Dauerwälzermüdung des Stahls R7T für Eisenbahnräder
2001
8 Seiten, 7 Bilder, 2 Tabellen, 9 Quellen
Aufsatz (Konferenz)
Datenträger
Englisch
Rolling contact fatigue of wheel and rail
Tema Archiv | 2012
|Wheel/rail rolling contact fatigue – Probe, predict, prevent
Tema Archiv | 2014
|Rolling contact fatigue of a rail steel
Tema Archiv | 1987
|Wheel-rail rolling contact theory
Tema Archiv | 1991
|