Modelling creep damage in heat affected zone in 321 stainless steel. Part II: Application to creep crack initiation simulations

Stabilized stainless steels like AISI 321 are well known to present a serious form of intergranular cracking in the HAZ referred to as reheat cracking. The purpose of the present part is to validate the creep damage model identified using the local approach methodology on notched bar creep tests (Part I) by checking if these damage laws are able to give accurate fracture predictions. The comparison between experimental data obtained at 600°C and numerical simulations is made for five different conditions with three different simulated HAZ and on two specimen geometries including CT specimen tested under stress relaxation conditions and sharply notched thin wall tubular specimens tested in torsion (Mode II loading). Both of these specimens have not been used for the identification of the damage model coefficients.