Author(s)

J. Wu, R. H. Petrov, S. Li, Z. Li, S. Godet, L. Malet, J. Sietsma

Abstract

Surface structural changes, formed during wheel/rail contact, in R260Mn grade rails were investigated by electron backscatter diffraction (EBSD), transmission Kikuchi diffraction (TKD) in scanning electron microscope (SEM) and automatic crystal orientation mapping in transmission electron microscope (ACOM-TEM). Grain fragmentation and refinement of ferrite are characterized by all applied methods as well as grain alignment towards traffic direction. Substructures, having misorientation lower than 5°, are identified by kernel average misorientation (KAM). Detection of retained austenite indicates martensitic nature of the structural change observed in the heavily deformed surface layer.

Keywords

surface structural change, brown etching layer (BEL), pearlitic rails, electron backscattered diffraction (EBSD), transmission Kikuchi diffraction (TKD), automatic crystal orientation mapping in transmission electron microscope (ACOM-TEM), martensite, ret