Published October 2012 | Version v1
Journal article

Characterization of grain boundary fracture in neutron-irradiated stainless steel by micro tensile test

  • 1. Inst. of Nuclear Safety System, Inc., Inst. of Nuclear Technology, Mihama, Fukui (Japan)
  • 2. Nippon Nuclear Fuel Development Co., Ltd., Oarai, Ibaraki (Japan)

Description

Characteristics of grain boundary fracture in stainless steel highly irradiated in a light water reactor was investigated by the micro tensile testing method. Micro tensile specimens containing a grain boundary were machined by the focused ion beam (FIB) technique for SUS316 stainless steel irradiated to 74dpa and then tensioned at room temperature in the FIB system. Brittle-like fracture occurred in one of two irradiated specimens, whereas fully ductile fractures occurred with high elongation in unirradiated specimens. From fractography by scanning electron microscopy, flat fracture surfaces and steps were observed on the irradiated specimen that had brittle-like fracture. Cross-sectional microstructural observation by transmission electron microscopy revealed that the grain boundary was fractured in this irradiated specimen. It was found that the grain boundary in highly irradiated stainless steel was fractured by stress concentration at the grain boundary due to accumulation of strain originating from twin deformation in the matrix. (author)

Additional details

Publishing Information

Journal Title
INSS Journal
Journal Volume
19
Journal Page Range
p. 155-165
ISSN
1340-4482

Optional Information

Notes
12 refs., 13 figs., 3 tabs.