Influence of a highly deformed surface layer on RCF predictions for rails in service
Year: 2025
Type: article
Abstract: Rolling Contact Fatigue (RCF) cracks often initiate from the surface layer of rails, where large accumulated plastic deformations influence the mechanical and fatigue properties of the rail material. Additionally, changes in profile geometry due to both plasticity and wear result in alternating contact locations and conditions. The goal of this study is to investigate the importance of considering these effects when predicting surface RCF crack initiation in rails. We analyze their individual impact on stress and strain fields, as well as fatigue crack initiation , by finite element simulations of railheads subjected to a mixed traffic situation. To account for deformation-dependent material behavior , an anisotropic plasticity model is calibrated against experiments with different amounts of accumulated shear strains measured in field samples. Finally, a recently developed crack initiation criterion is employed that accounts for the influence of plastic deformations . Under extreme loading conditions, i.e., full slip with a traction coefficient of 0.4, it is shown that both deformed near-surface material and deformed geometry reduce the predicted RCF fatigue damage significantly, by factors of about 5 and 30, respectively. Furthermore, not accounting for the combined effect of deformed material state and geometry leads to approximately 150 times larger predictions of RCF damage.
Source: Wear
Institution: Chalmers University of Technology
Language: English
Subfield: Mechanical Engineering
Field: Engineering
Domain: Physical Sciences
Open Access status: hybrid
Estimated APC paid: $5,394
OpenAlex ID: W4411349113