Analysis of stress intensity factors in railway wheel under the influence of stress field due to heat treatment and press-fitting process

Railway transportation system is one of the main needs of the population living in industrialized countries. Many studies have been conducted by engineers due to the importance of railway wheels and railways as a major part of the train. But due to progress in railway technology, in recent years a new type of train wheel known as rim-wheels is presented that their fracture is investigated in this study. The goal of the present study is to calculate stress intensity factors numerically using the boundary element method in railway wheels based on experimental data of material behavior. For this purpose, a series of experiments were performed to determine the behavior of the railway wheel material as well as the data required for numerical analysis. The innovation of this research is that the stress intensity factor is calculated resulting from residual stress of press-fit and heat-treatment processes. Then, the stress intensity factors resulting from the two processes are superimposed in pure mode I, mode II, and mode III loading due to the same crack geometries. Also, the study includes a survey on the effect of crack length on crack propagation as one of its main effective factors. Besides, fatigue crack growth path is calculated and its propagation is also estimated and the effect of different parameters is studied on fatigue crack growth and path.