Component compatibility

Satisfactory performance of in-core components requires compatibility with the reactor coolant. Rates of environmental attack must be measured as a function of temperature, coolant composition, irradiation, and metallurgical condition. The morphology of reaction products should be investigated, since localised attack may have an adverse effect on thin structures. The ability of the oxide to continue to grow at interfaces must also be determined. Reaction rates and the adherence of corrosion products need to be assessed for sensitivity to temperature and strain cycling likely to be encountered in service. Corrosion/wear interactions and static adhesion must also be considered for some components. Finally, if service conditions are likely to be severe, the materials evaluation programme must examine the influence of environment on tensile, creep and fatigue properties. (author)