Effect of Notch on Creep Behavior of 316L(N) SS Weld Joint

Creep testing of notched cross-weld specimens was carried out at 873 K temperature and 300 MPa stress to study the effect of notch on creep properties of 316 L (N) SS weld joint. Various stress states were achieved by changing the notch profile. It was observed that, multiaxial state of stress developed during creep had a decisive role in creep life and the deformation mechanism. Thus, presence of notch and its consequences on creep life of the specimen prompted to offer exact solutions to explain the creep behavior. Notch strengthening effect is reported in the present investigation. Single mode of fracture was observed and fractures were located at the notch root. The transformation of δ-ferrite to sigma phase during creep exposure for about 2700 to 6200 h had resulted in ductile fracture in weld metal.