Corrosion problems in the nuclear power industry and implications for the future

The objective of this review is to evaluate the history of important corrosion problems that have occurred in materials in light water nuclear power plants in order to identify the lessons that should be learned to prevent recurrence. These major corrosion problems are summarized and their causes are described. Two significant problems are emphasized: (1) intergranular stress corrosion cracking (IGSCC) that has affected regions adjacent to welds in austenitic stainless steel in boiling water reactors (BWRs); (2) IGSCC that has been sustained by Alloy 600 used both as steam generator tubes and as reactor coolant system penetrations in pressurized water reactors (PWRs). This review discusses the technical bases that were used at the time of the selection of these materials together with the subsequent failures that occurred in service and the problems with the original technical bases. Institutional factors that contributed to the selection of materials that experienced severe corrosion problems are discussed. Implications from these problems for future applications are discussed where failures have major impacts on economics, safety or operation.