Please consider attending the following: MATERIALS ENGINEERING SEMINAR "Three Dimensional Characterization and Modelling of Irradiation Effects in Austenitic Stainless Steels for Nuclear Applications" By Sri Tapaswi Nori Purdue MSE Ph.D. Preliminary Exam Advisor: Professor Maria A. Okuniewski ABSTRACT Austenitic stainless steels have been qualified as structural materials in a nuclear reactor core due to their good high-temperature strength and corrosion resistance. However, the conventional 300 series alloys cannot endure the unusual combinations of high temperatures, neutron radiation dosages and stresses in Gen-IV nuclear reactors. In this context, high temperature ultrafine precipitation strengthened steel (HT-UPS) was developed and is being projected to be suitable for these advanced reactors because of its high temperature creep resistance. However, little is currently known about its radiation tolerance. Neutron irradiation induces defect structures over multiple length and time scales. High-energy X-rays can be employed to study this microstructural and micromechanical evolution under irradiation, as they provide three dimensional and non-destructive characterization. A review on some of these techniques like far-field high-energy diffraction microscopy (FF-HEDM) and near-field high-energy diffraction microscopy (NF-HEDM) will be presented and their application to the study of irradiation effects in HT-UPS at a mesoscale level, will be discussed. Phase field models have emerged as right numerical tools to simulate irradiation effects and these will be briefly introduced. In the context of studying neutron radiation damage response of HT-UPS, both the phase field models and the characterization techniques mentioned earlier will be utilized. Date: Tuesday, January 9, 2018 Time: 10:00 A.M. Place: EE 224