Material corrosion in high temperature aqueous solutions in power generating systems

The corrosion of structural materials in high temperature aqueous environments is reviewed with reference to problems encountered in the nuclear and geothermal power industries. Emphasis is placed on identifying the causes and remedial measures for: (1) Pitting of stainless steels in geothermal brines, (2) Intergranular stress corrosion cracking of Type 304 SS under simulated Boiling Water Reactor (BWR) heat transport circuit conditions, and (3) Irradiation assisted stress corrosion cracking of in-core components in water cooled nuclear reactors. Experimental methods for investigating these phenomena are described and various experimental results are reviewed to indicate the mechanisms of the corrosion processes. Particular attention is paid to the use of electrochemical techniques for studying corrosion processes in high temperature aqueous systems because they have contributed greatly to the development of remedial measures. Finally, we comment on the institutional problems facing corrosion science and engineering, particularly in the nuclear industry where our failure to properly consider the impact of corrosion phenomena has extracted an enormous price from reactor operators and consumers and has contributed significantly to the public's mistrust of nuclear power. (A)