Stress Corrosion Behavior of Welded Joints of Stainless Steel in Nuclear Power Plants

Constant load stress corrosion test, constant deformation stress corrosion test and slow stain rate test (SSRT) were conducted to study the stress corrosion behaviors of welded joints of S30403, S32101 and S32205 stainless steels under the condition of boric acid solution. The results show that the three stainless steel joints did not fracture after constant load stress corrosion test and constant deformation stress corrosion test for 720 hours. The sequence of stress corrosion resistance of the three joints were S32205>S32101>S30403 in SSRT. The decrease of pH and the increase of Cl^- concentration, temperature and oxygen concentration could improve the stress corrosion sensitivity of the three stainless steel joints. And pH had more significant effect than the other three factors.