Thermal, irradiation and cyclic loading analysis for stress fatigue crack in reactor vessels

Abstract

The thermal, irradiation and cyclic loading analysis for stress fatigue crack (SFC) of the base and weld materials of LMFBR (liquid metal fast breeder reactor) and LWR (light water reactor) pressure vessels is theoretically carried out based on experimental data. The power function and exponential function crack (rate) laws and the SFC theory are introduced and postulated for the stress intensity factor, K, or the effective stress intensity factor, K eff , versus the fatigue crack growth rate in the vessel materials. Experimental data of austenitic stainless steels 304 and 316, nickel alloy Inconel 600, and low-carbon alloy steels A516 and A533 of the LMFBR and LWR pressure vessels were respectively computedly measured, examined and analyzed, and then plotted for either power function crack rate and/or exponential function crack law. The theoretical prediction and the computerized experimental data are in excellent agreement. These results can be applied in the respective LMFBR and LWR pressure vessel design, construction, operation and lifetime prediction in a fast or thermal nuclear power reactor to generate electricity.