Local strain distribution near grain boundaries under tensile stresses in highly irradiated SUS316 stainless steel

Local strain near grain boundaries under tensile stress was examined using the EBSD technique for cold-worked SUS316 stainless steel irradiated to 73 dpa. Distribution of misorientation in the same areas was analyzed while macroscopically deforming the specimen at an elastic strain level of 0.03% and a plastic strain level of 3%. A clear increase in local strain was detected within 4 μm from the grain boundaries at the 3% plastic strain. It was confirmed that high local strain was produced at the 0.03% elastic strain near the grain boundaries which exhibited higher misorientations at the plastic strain. Detailed analysis in areas within 1 μm from individual grain boundaries also revealed that local strain was increased at some boundaries at the 0.03% elastic strain.