On wheel-rail contact surface phenomena with structural changes and white etching layers generation

Abstract

The main aim of this work was a study of the microstructure transformations with the residual stress formation that is induced by rolling contact friction and adhesive wore in the wheel-rail system. Several small railsurface samples, we term them as the chips, and a piece of wheel sample were chosen for the analyses of the surface changes on the wheel-rail surface. A multitude of different experiments were carried out in order to analyse the microstructure changes at the surface and the near-surface region of the material samples and, thus, to contribute to the understanding of the complex wheel-rail rolling contact phenomena - and its degradation mechanisms. The formation of nano-structured martensite and carbides on the rail and wheel surface causes the extremely high microhardness valuees and the strong corrosion resistance of the so called White Etching Layers (WEL). © 2012 Copyright Vilnius Gediminas Technical University (VGTU) Press Technika.