ADVANCED STEELS FOR ACCIDENT TOLERANT FUEL CLADDING IN COMMERCIAL NUCLEAR REACTORS

摘要

After the March 2011 events at the Fukushima site, the U.S. congress directed the Department of Energy (DOE) to focus efforts on the development of fuels with enhanced accident tolerance. In comparison with the standard U02-Zircaloy system, the new fuels need to tolerate loss of active cooling in the core for a considerably longer time period while maintaining or improving the fuel performance during normal operations. A GE Global Research 1ed program is investigating the behavior of advanced steels both under normal operation conditions in high temperature water (e.g. 288°C) and under accident conditions for reaction with steam. Results show that, under accident conditions, the advanced steels: (1) have low reactivity with steam, (2) would generate less hydrogen than the current zirconium based alloys, (3) offer higher mechanical properties, and (4) offer excellent retention of fission products. These advanced steels are also highly resistant to environmental cracking under normal operation conditions and they are not susceptible to suffer irradiation damage such as void swelling.