Abstract
Abstract The crack closure phenomenon is important to study as it estimates the fatigue life of the components. It becomes even more complex under low-cycle fatigue (LCF) since under LCF high amount of plasticity is induced within the material near notches or defects. As a result, the assumptions used by the linear elastic fracture mechanics (LEFM) approach become invalid. However, several experimental techniques are reported on the topic, the utilization of numerical tools can provide substantial cost and time-saving. In this study, the authors present a finite element simulation technique to evaluate the opening stress levels for two structural steels (25CrMo4 and 30NiCrMoV12) under low-cycle fatigue conditions. The LCF experimental results were used to obtain kinematic hardening parameters through the Chaboche model. The finite element analysis (FEA) model was designed and validated, following the fatigue crack propagation simulation under high plasticity conditions using abaqus. Crack opening displacement versus stress data were exported from abaqus, and 1.5% offset method was employed to define opening stress levels. Numerical simulation results were compared with the experimental results obtained earlier through the digital image correlation (DIC) technique. To conclude, FEA could be a valuable tool to predict crack closure phenomena and, ultimately, the fatigue life of components. However, analysis of opening stresses using crystal plasticity models or extended finite element method (XFEM) tools should be explored for a better approximation in future studies.
Highlights
Railways serve as actual freight and passenger carrier transportation modes
The results revealed that a strong correlation existed between low cycle fatigue (LCF) and magnitude stress
After simulating three strain ratios, at which material was tested during digital image correlation (DIC) experiments, the stabilized hysteresis loops were compared with experimental results
Summary
The railway axles contribute as the primary load-carrying element; the design of railway axles and the study of their mechanical behavior under repeated loading is vital. The safe and reliable design of railway axles is indispensable to assure the safety of vehicles and passengers. The fatigue life cannot be determined for parts experiencing low cycle fatigue (LCF) using this approach due to high plastic deformations involved. The interest in the study of fatigue strength of railway axles has significantly increased [1]–[4]. The crack opening load is mostly determined under both low and high cycle fatigue by various experimental techniques [5]–[9] and numerical methods [10]–[14]. In the case of complexities, Finite element analysis (FEA) is a prime choice over an experimental approach
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
