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Abstract: Creep testing of notched cross-weld specimens was carried out at 873K temperature and 300MPa 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 6200h had resulted in ductile fracture in weld metal. [Copyright &y& Elsevier]

Abstract: Creep tests on 316 L (N) stainless steel notched specimens with varying notch acuity were carried out and notch effect was studied. Various multiaxial stress states were generated by providing circumferential V-notch. The tests were car ied out under load of 300MPa and at 873K temperature. The creep life of notched specimens was found to be in the range between 1500-3800hours. Material exhibited notch strengthening effect which was attributed to the multiaxiality resulting into stress distribution during creep. Mixed mode of fracture was observed. The scanning electron micrographs revealed that, the location of transition from brittle to ductile mode was pulled in towards center of cross-section as the degree of constraint was reduced. Finite element analysis results showed that, the stress distribution was a local event in the highly constrained specimen and a global event for specimen having lower constraint. [Copyright &y& Elsevier]

Abstract: The present work focuses on testing of 316 L (N) steel in which varying degrees of multiaxiality are introduced with variation in the stress intensity factor, Kt. The specimens were tested under varying notch geometries at 873K and 300MPa. The stress distributions from the notch root to center of the specimen are explained with Finite Element Modeling calculations simulated later with ANSYS software. Correlation of the stress distribution with microstructural features is attempted to evaluate stress offloading due to multiaxiality. [Copyright &y& Elsevier]