CRACK-GROWTH BEHAVIOR IN 316FR STAINLESS-STEEL PLATE UNDER TENSILE-BENDING LOADING AND ITS SIMPLIFIED EVALUATION

As a part of the efforts for developing reliable structural integrity assessment methods for Fast-Breeder Reactor(FBR) components, cyclic cr ack growth tests at 550 degrees C were conducted for large plate speci mens of 316FR stainless steel under combined tensile-bending loads. Cr ack growth became slowly and its shape became shallower with increasin g of the ratio of the bending to membrane stress. A crack growth analy sis was carried out using a nonlinear fracture mechanics parameter, cy clic J-integral range. A simplified method based on the reference stre ss concept was used to calculate cyclic J-integral range. The applicab ility and possible improvement of the simplified method were discussed using test results.