Metal alloy coating for reducing stress corrosion cracking of metal parts in high temperature water

摘要

A method for mitigating crack initiation and propagation on the surface of metal components in a water-cooled nuclear reactor. A metal coating having an electrically insulating outer layer is applied on the surfaces of IGSCC-susceptible reactor components. The preferred metal coating is a zirconium alloy with a zirconia outer layer. The presence of an electrically insulating layer on the surface of the metal components shifts the corrosion potential in the negative direction without the addition of hydrogen and in the absence of a noble metal catalyst. Corrosion potentials/=-0.5 VSHE can be achieved even at high oxidant concentrations and in the absence of hydrogen.