Research on Corrosion Behavior of Stainless Steel Cladding Welding Simulator in Nuclear Power Plant

The corrosion behavior of the welding simulators of three stainless steel cladding materials S32205, S32101 and S30403 in spent fuel pool of nuclear power plant was studied by soaking them for 6 months under the conditions of H₃BO₃ concentration of 2500 mg/L, SO₄²⁻ concentration of 1500 mg/L, Cl⁻ concentration of 5%, pH value of 5.0, temperature of 80 ℃ and saturated oxygen. The results show that a large number of chlorine induced stress corrosion cracks appear near the welding joints and gaps of S30403 welding simulator; S32101 welding simulator has corrosion pits, especially near the welding joints and gaps; S32205 welding simulator has the lightest corrosion, and no corrosion pits and cracks are found on the surface of the test piece. The research shows that the corrosion resistance law of the three material simulator is: S32205>S32101>S30403. S32205 has good comprehensive mechanical properties and corrosion resistance, is an ideal improved pool cladding material.