Studies on corrosion failure of components in PWRs in the science and technology on reactor fuel and materials laboratory

Corrosion of nuclear materials is a major issue for plant safety and economic competitiveness of the nuclear industry. Science and Technology on Reactor Fuel and Materials Laboratory has focused on the study of variety forms of corrosion issues such as SCC, IGSCC, IASCC, and FAC etc. since its establishment. This report introduces the major present works of the lab from three aspects: general mechanism of material corrosion, corrosion failure case studies in nuclear power plants and corrosion degradation management of structural materials of the key components. This report interprets some important corrosion failure issues in detail. These cases include the oxygen lead SCC in the bending tubes of primary loop; the IGSCC of primary loop tubes caused by specific operation conditions, new findings in alkali lead SCC of 690, and corrosion of shaft and SG tubes due to the inappropriate maintenance. All these cases are of important reference values to the corrosion protection and management in NPPs in China. (author)