The objective of this work is to investigate the microstructure evolution railway pearlitic wheel materials (ER7, CL60 and C-class) under a rolling-sliding contact loading. Firstly, microstructures steel at different depths from strain-free matrix top surface were systematically investigated via laser scanning confocal microscope (LSCM), electron microscopy (SEM), backscattered diffraction (EBS...

In this paper, the gear material 20CrMnTi was selected as the research object. Friction and wear behavior was performed on the M2000 friction and abrasion tester. The friction and wear mechanisms of 20CrMnTi steel were discussed under coupling of rolling and sliding. The results show that damage of steel-steel couples under coupling of rolling and sliding is caused by the interaction of mechani...

Rolling contact fatigue tests on 100Cr6 steel were carried out with a ballon-rod tester. Microstructural damage was manifested by gradual hardness changes under the subsurface, and microcracks formed adjacent to inclusions; both being evidence of plastic deformation. The hardness increase appears to be due to the development of residual stress, while the microcracks form as a result of the conc...

The behaviour of sound waves interacting with wedges has attracted interest from researchers in geophysics and non-destructive testing. We consider here the nearfield behaviour of Rayleigh waves incident on wedges and surface-breaking defects which propagate at an angle to the surface, such as rolling contact fatigue on rails. It has been shown that, for a detection point on the edge of the cra...

Temper rolling or skin pass rolling is one of cold rolling processes composed of a horizontal pass cold rolling mill stand. In this process, the thick strip is subjected to very light reduction (0.5–4%) in thickness in the presence of high friction amplitudes. One of the basic parameters of strip rolling processes is temper rolling force. A new rolling force model has been proposed for temper r...

This paper discusses the use of Linear Mixed Models (LMM) and Generalized Linear Mixed Models (GLMM) to predict the wear and damage trajectories of railway wheelsets for a fleet of modern multiple unit trains. The wear trajectory is described by the evolution of the wheel flange thickness, the flange height and the tread diameter; whereas the damage trajectory is assessed through the probabilit...

This paper presents a strategy to predict the lifetime of rails subjected to large rolling contact loads that induce ratchetting strains in the rail head. A critical element concept is used to calculate the number of loading cycles needed for crack initiation to occur in the rail head surface. In this technique the finite element method (FEM) is used to determine the maximum equivalent ratchett...

Computation of contact point trajectories and forces exchanged between two bodies in contact are relevant to several disciplines. The solutions proposed in the literature are often too complex to be implemented in real time simulations, especially if rolling effects are considered. In this chapter, an algorithm for fast simulation of softfinger contact model with rolling effects is proposed. Th...