Creep-Fatigue Life Evaluation of HR6W (23Cr-45Ni-6W) Base Metal and Welded Joint

Creep-fatigue life evaluation method for HR6W base metal and welded joint was examined based on the results of uniaxial fatigue creep-fatigue tests using smooth specimens at 700 750℃. Regarding metal, by linear damage rule carried out test with strain holding time up to 10 hours. In case fraction rule, failure criterion intersection (Df , Dc) = (0.1 0.1) gave conservative prediction even in long ductility exhaustion model, other hand, reduction increase expressed well including dependence range. With respect joint, shorter than that although cracks were observed near fusion line under all conditions. From both FEM analysis DIC (digital image correlation) measurement during test, this found be caused concentration due longitudinal variation stress-strain behavior joint. Fatigue could predicted curve factor obtained from analysis.