Corrosion Behavior of Steel Liner Plate in Boric Acid Solution Used in Nuclear Power Plant

Intergranular corrosion test, electrochemical test and stress corrosion test were used to study the corrosion behavior of pool steel liner S32205, S32101 and S30403 in the boric acid solution of nuclear power plants. The results showed that the intergranular corrosion tendency of the three materials under given test conditions was small. Crevice corrosion potential and protection potential of S32205 stainless steel were the highest, which were 0.64 V (vs. SCE, the same below) and 0.1 V, respectively. The crevice corrosion potentials of S32101 and S30403 stainless steels were almost the same, about 0.25 V. The protection potential of S30403 stainless steel (0 V) was slightly higher than that of S32101 stainless steel (-0.1 V). The crevice corrosion resistance and stress corrosion resistance of the three materials were S32205 stainless steel > S32101 stainless steel > S30403 stainless steel, and all the three materials did not fracture after the constant load stress corrosion test.