Prediction of ductile fracture in modified 9Cr-1Mo steel at intermediate stress triaxiality using void growth model

The void growth model parameter for Modified 9Cr-1Mo steel has been identified based U-notched tensile tests, scanning electron microscopy study on fracture surface and parallel 3D FEM simulations. Damage Index (DI) symptomatic of Rice-Tracy VGM parameter at a large number of sampling points in micro void coalescence zone is calculated for increase in applied loads. The calculated DI has been calibrated with experiments on specimens with through wall central notches oriented at different angle to loading axis.