b'3.2 CORE MATERIALSMechanical Testing of High Dose Irradiated Materialsfor Fast Reactor ApplicationsPrincipal Investigator: Benjamin P. Eftink (LANL)Team Members/ Collaborators: Matthew E. Quintana, Tobias J. Romero, Paul L. Caccamise, Tarik A. Saleh and Stuart A. Maloy (LANL); Cheng Xu (TerraPower, LLC); Gary Was (University of Michigan)F erritic/martensitic (FM) steels and nanostructured ferritic alloys (NFA) are being developed for next generation high dose reactor applications. Applications such as transmutation of long lived isotopes in used fuels require cladding materials that can withstand high irradiation doses, potentially in the hundreds of displacements per atom (dpa), at intermediate to elevated temperatures and in contact with a liquid metal coolant. Changes in the mechanical properties occur after such harsh conditions. Mechanical testing as part of this project probes changes in mechanical properties due to neutron irradiation of fast reactor relevant alloys.Project Description: The main technical objectives of the project include: i) determining the changes to mechanical properties of advanced ferritic steels (such as oxide dispersion strengthened (ODS) steels 14YWT and MA957) Figure 1. Image of hot cell at Losto high dose irradiations ii) deter-Alamos National Laboratory (LANL)mining the changes to mechanical in CMR Wing 9 where mechanicalproperties of traditional ferritic/testing occurred.martensitic steels (such as HT-9 or T-91) to high dose irradiations iii) understanding the effect of irra-diation temperature on irradiation 178 2019|AFC ACCOMPLISHMENTS'