The objective of this talk is to reveal the influence of irradiation defect microstructures on deformation mechanisms in face centered cubic (fcc) alloys. Concentrated solid-solution fcc alloys form the basis for the most ubiquitous structural materials used throughout society (e.g. stainless steels), and for novel alloy concepts such as high entropy alloys. When these alloys are exposed to far-from-equilibrium irradiation conditions, they evolve microstructures containing a complex distribution of point defects (vacancies and interstitials) and extended defects such as dislocation loops and voids. These defects are well known to pin dislocations during plasticity, leading to hardening and embrittlement. But recent studies have suggested that these defects can also activate low-temperature deformation mechanisms including twinning and diffusionless solid-state (i.e., martensitic) phase transformations. This work will use simulations to reveal how defects control deformation mechanisms, with complementary experiments to illuminate irradiation-deformation microstructures.
Janelle P. Wharry is an Associate Professor in the School of Materials Engineering at Purdue University and Editor of Materials Today Communications. Dr. Wharry’s research aims to understand structure-property-functionality relationships in irradiated materials, with an emphasis on deformation mechanisms and mechanical behavior at the nano/microscale. Her active projects span nuclear structural and cladding alloys, structural materials produced by advanced manufacturing and joining methods, metal and oxide nuclear fuels, and electroceramic materials. She has published 90 peer-reviewed journal articles and conference papers. Dr. Wharry’s work in nano/micro-mechanical behavior of materials has earned several awards, including the Department of Energy (DOE) Early Career Award, National Science Foundation CAREER Award, and American Nuclear Society (ANS) Landis Young Member Award. She serves as Chair of ASTM International Subcommittee E10.08 on Procedures for Radiation Damage Simulation. She received her Ph.D. in Nuclear Engineering & Radiological Sciences from the University of Michigan in 2012.