Fatigue life estimation of cast components

An engineering method based on fracture mechanics is suggested for life pre dictions of components of nodular cast iron. The method should be applicabl e to any structure containing defects which can cause crack initiation. Com ponent testing was performed and the observed results were compared with mo del predictions. Fatigue crack growth data were obtained by testing on CT s pecimens even for load ratios R < 0. By accounting for crack closure the R- effect on the growth rates can also be effectively eliminated for this type of material.