疲労き裂開閉口挙動の残留応力的検討

抄録

The distribution of residual stress in the vicinity of fatigue crack tips and behind them of S15C, SK-5 were measured by X-ray microbeam equipment. Fatigue cracks were loaded and unloaded and then the behaviors of opening and closing were examined analytically. The results obtained are summarized as follows. (1) A monotonic plastic zone ahead of the crack tip and a cyclic plastic zone was found in the vicinity of crack tip. (2) It was found that the ratios of fatigue crack opening and closing by X-ray measurement were in good agreement with the value by the micro displacement method.