Radiation embrittlement: significance of its effects on integrity and operation of LWR pressure vessels

The significance of radiation embrittlement of reactor pressure vessel materials is discussed relative to the integrity and operation of the early-generation light-water-reactor systems. The economic impact of exceeding the current embrittlement limits imposed by federal regulations is estimated. The embrittlement limits are evaluated in terms of actual reactor integrity considerations. The saturation of radiation embrittlement phenomenon is described, with supporting experimental and analytical evidence. Finally, the impact of the embrittlement saturation on the operation of the early-generation nuclear plant is assessed.