1990 Volume 30 Issue 10 Pages 847-853
In order to understand the correlation between creep crack growth rate and microscopical fracture mechanism, creep crack growth tests were carried out using CT specimens on 316 stainless steel at various temperatures and stresses. Three kinds of fracture mechanisms, i.e., 1) wedge-type intergranular fracture (W-type), 2) transgranular fracture (T-type), 3) cavity-type intergranular fracture (C-type), were observed depending on testing conditions. Creep crack growth rate was evaluated by C* parameter. For a given C* value the creep crack growth rate in W- and C-type fracture modes was higher than that in T-type fracture mode. The relationship between creep crack growth rate and C* value for these fracture modes was discussed concerning creep properties, creep ductility and microscopical feature ahead of crack tip.
