Simulation of Stress-Corrosion Cracking by the Cohesive Model

Abstract

The effect of hydrogen on the mechanical behaviour is twofold: It affects the local yield,stress and it accelerates material damage. On the other hand, the diffusion behaviour is influenced,by the hydrostatic stress, the plastic deformation and the strain rate. This requires a coupled model,of deformation, damage and diffusion. The deformation behaviour is described by von Mises,plasticity with pure isotropic hardening, and crack extension is simulated by a cohesive zone model.,The local hydrogen concentration, which is obtained from the diffusion analysis, causes a reduction,of the cohesive strength. Crack extension in a C(T) specimen of a ferritic steel under hydrogen,charging is simulated by fully coupled diffusion and mechanical finite element analyses with,ABAQUS and the results are compared with test results.