抄録
Potentiostatic etching method has been suggested as a technique for detection of pre-existing plastic strain of type 316 stainless steel which is strained at 250℃ that is a temperature assumed nuclear reactor water. After potentiostatic etching (1N HNO_3, -600mV_<SCE>, 20min, 35℃), slip lines appear as etched lines on the surface of specimen, and their density has one-to-one correlation with pre-existing strain. However, it is difficult to count the number of etched lines originated in slip lines because they are not clear. In this study, optimal electrochemical potential and exposure time which make counting easy have been investigated. As a result, electrochemical potential and exposure time are estimated -675mV_<SCE> and 10 minutes, respectively.
