Analysis of fatigue crack growth under mixed-mode loading conditions for a pearlitic Grade 900A steel used in railway applications

Abstract

The purpose of this paper is to present a new method for estimating the fatigue life of engineering components using the rigid-insert crack closure (RICC) model under mixed-mode cyclic loading conditions. For this purpose, the method of solving the RICC model has been changed from pure mode-I cyclic loading condition to mixed-mode cyclic loading conditions. The new method is applied to compact tension shear (CTS) specimens that has the same conditions as engineering components. The application of the new applied method has been evaluated for railway rail using numerical analysis and experimental tests. Numerical analysis has been performed using linear elastic fracture mechanics (LEFM) and boundary element method. Also, the fatigue fracture surface of CTS specimens are analyzed using scanning electron microscope (SEM) to evaluate the effect of different loading angles. Finally, the results of the new applied method for fatigue life are compared with experimental tests and numerical method that results in acceptable achievements.