炭素鋼表面き裂材の腐食疲労き裂進展挙動に関する破壊力学的研究

抄録

In order to investigate the characteristics of surface crack growth behavior, the fatigue test and potential measurement using a simulated surface crack specimen for low-alloy steel (STS-42) were achieved in pure water at a temperature of 50°C and an oxygen content of 2 ppm. The potential observed in the surface crack plane showed that the differences depended on the crack depth. With time, the potential around the. crack surface showed more noble values than at the deepest tip of crack This reason could be explained by the difference in oxygen content along the crack plane due to the effect of water flow and crack shape. The mechanism of the generation of the hydrogen-assisted intergranular fracture mode observed at crack surface was also discussed based on an electrochemical aspect.