b'Assessment of IrradiationSmall-scale thermal and irradiation creep measurements Creep Using Acceleratoraccelerate advanced materials development.Technology to Down-selectA dvanced materials with enhanced resistance to irradiation at high temperatures benefit the life-extension and long-term operation of Materials for In-pile Testingthe current light water reactor fleet and the development of advanced nuclear reactor concepts. To qualify a material for reactor operation, many mechanical properties must be assessed, including thermal and irradiation creep. Creep is a time-dependent deformation process for a metal under the influence of stress, temperature, and irradiation. It is important to assess all aspects of the creep properties of new materials for reactor applications: thermal creep of PROJECT NUMBER:as-manufactured materials, in-reactor/irradiation creep, and thermal creep of 20A44-155 irradiated materials. In this project, accelerated creep measurement techniques were developed to assist in rapid qualification of new reactor materials. Those TOTAL APPROVED AMOUNT:techniques include nanoindentation creep testing, mesoscale thermal creep testing $950,000 over 3 years and small-scale proton irradiation creep testing. In the nanoindentation testing, PRINCIPAL INVESTIGATOR:the creep of oxide-dispersion-strengthened stainless steel was performed and Wen Jiang characterized. The nanoindentation modeling with Multiphysics Object-Oriented Simulation Environment (MOOSE) was used to extract the creep properties from the CO-INVESTIGATORS: nanoindentation creep data. The novel mesoscale creep experiments on zirconium-Boopathy Kombaiah, INLniobium specimens with sizes of tens of micrometers were performed to extract Cheng Sun, INL bulk creep properties. Their measured rate of deformation shows good agreement Colin Judge, INL to the bulk creep testing data. The in situ irradiation creep of 304 stainless steel was COLLABORATOR: demonstrated using proton irradiation facilities at Michigan Ion Beam Laboratory. University of Michigan The irradiation temperature, strain, load, and proton beam current were recorded to obtain creep properties. This project paved a way to obtain creep properties of materials using only a small volume of specimen, facilitating efficient use of precious neutron-irradiated materials. This will significantly shorten the nuclear fuel and material development cycle and expedite the deployment of advanced materials for in-core applications.28'