DCPD and strain gauge based calibration procedure for evaluation of low temperature creep behavior

Creep cracking is one of the key forms of structural material SCC damage with respect to nuclear power. Accurately obtaining the amount of creep deformation is also an important basis for estimating the service life of structural parts. However, because the primary circuit of nuclear power occurs in a high-temperature and high-pressure service water environment, it is not possible to use a conventional extensometer to obtain accurate creep of gauge length under these conditions. Considering that DCPD is an important method for monitoring crack propagation in a high-temperature water environment, by taking the austenite 304 stainless steel commonly used for nuclear power as a research object, a calibration method based on a combination of DC potential drop (DCPD) and strain testing to obtain the creep deformation of the specimen was established. By comparing theoretical research with experimental results, it can be concluded that the calculation results of the model are close to the experimental results and consistent with the theory, thus proving the feasibility of using DCPD technology to obtain the creep deformation amount.