Rate Sensitivity in Irradiated HT-9 for Reactor Applications

The Fuel Cycle Research and Development program is investigating methods of burning minor actinides in a transmutation fuel through various fuel cycle options. To achieve this goal, the fast reactor core materials (cladding and duct) must be able to withstand very high doses (>200 dpa) while in contact with the coolant and the fuel. In order to develop physicsbased models of cladding materials for fast reactor applications, more specific testing is required in addition to typical tensile testing. Analysis of a duct made of HT-9 after irradiation to a total dose of 155 dpa at temperatures from 370 to 510 degree C is almost complete including tensile, charpy impact and fracture toughness testing. Specific rate jump tests are underway to investigate rate sensitivity before and after irradiation. Detailed microstructural analysis has also been performed with TEM. A summary of rate sensitivity will be presented in connection with detailed analysis of controlling defects.