Interpretation of SSOUFFLE experiment : Comparison of the JNC and CEA approaches

Laurent LE BER*; kasahara, Naoto

For considering strength reduction of weldments in elevated temperature components, CEA and JNC have developed design evaluation procedures, Both procedures were applied to the same benchmark problems and their results were compared under EJCC contract. One of benchmarks that provided by CEA is creep-fatigue evaluation of plates subjected to cyclic bending. The objective of this problem is comparison of both material data and strength reduction evaluation of welded joints. When applied to SOUFFLE experiments, JNC and CEA evaluation procedures were clarified to give adequate predictions. Comparison of material data between Japanese 316FR and French 316L(N) showed such similar characteristics as strain hardening of base metai, non-strain hardening of weld metal and approximately the same fatigue strength of weld metal with its base metal. Both fatigue strength approaches were different, since JNC considers material difference between base and weld metal for strength reduction of welded joints and CEA evaluates fatigue strength reduction of weld metal. Concerning creep strength, both of JNC and JEA take strength reduction of weld metal into account.