|About this Abstract
|MS&T23: Materials Science & Technology
|Interface-mediated Phenomena in Structural Materials
|Understanding Grain Boundary Segregation in FeCr Alloys: Multiscale Modeling and Experiments
|Sourabh Bhagwan Kadambi, Mukesh N Bachhav, Boopathy Kombaiah, Jia-Hong Ke
|On-Site Speaker (Planned)
|Sourabh Bhagwan Kadambi
Grain boundaries (GBs) are a crucial component in the design of irradiation resistant materials due to their role as sinks for non-equilibrium point defects. However, the coupled transport of atomic components with inherently different diffusivities often leads to radiation-induced segregation (RIS), with undesired effects such as intergranular corrosion and stress-assisted cracking. In this talk, we investigate fundamental mechanisms of Cr segregation in BCC FeCr-alloys using multiscale modeling and experiments. A phase-field model is employed to account for both thermodynamic and kinetic segregation mechanisms. The full Onsager transport matrix is derived using kinetic Monte Carlo, molecular dynamics, and kinetic cluster expansion (KineCluE). Thermodynamics of GB segregation is described via an atomic density-based CALPHAD free energy function. Modeling predictions are compared against segregation data from atom probe characterization for various temperatures, compositions, and neutron irradiations. We will conclude by discussing the utility of the multiscale approach for elucidating solute-GB interactions under irradiation.