A method for mitigating stress corrosion cracking in nuclear plant structural materials.

摘要

PPROBLEM TO BE SOLVED: To improve integrity of a plant by suppressing increase in stress corrosion cracking sensitivity by suppressing increase in electric conductivity. PSOLUTION: In an operation of a boiling water nuclear power plant, a material for reducing the concentration of oxygen or hydrogen peroxide in reactor water by chemically reacting with the oxygen or hydrogen peroxide is injected into the reactor water. During stop of the operation, a layer of a compound having a spinel type structure composed of bivalent metal ions and trivalent iron ions is formed on a heat transfer surface of a feed water heater. Even when hydrogen injection or the like to the reactor water is stopped, increase in chrome ion concentration in the reactor water can be suppressed. As a result, the electric conductivity can be suppressed, and increase in sensitivity to stress corrosion cracking can be suppressed. PCOPYRIGHT: (C)2007,JPO&INPIT