|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Grain Boundaries and Interfaces: Metastability, Disorder, and Non-Equilibrium Behavior
||Unraveling Mechanisms of Interface Diffusion and Interfacial Creep in Metals and Metal-ceramic Composites
||Ian Chesser, Raj Koju, Yuri Mishin
|On-Site Speaker (Planned)
Interface diffusion and interfacial slip are two key processes controlling the high-temperature creep deformation of metal-matrix composites. Fundamental understanding of these processes remains poor. Atomistic simulations are a promising route toward understanding, but reliable methodology for measuring kinetic coefficients and disentangling competing mechanisms has not been developed in this context. In this work, we compare interface diffusion and sliding coefficients in pure Al and Si grain boundaries to those in AlSi phase boundaries using direct molecular dynamic simulations at high and intermediate homologous temperatures. Interface diffusion and interface slip are shown to be distinct, but correlated processes with characteristic fractal dimensions, cluster size distributions, and nucleation and growth dynamics. Diffusion and sliding mechanisms are analyzed over a large parameter space including multiple interface geometries, temperatures and strain rates.
||Thin Films and Interfaces, Mechanical Properties, Ceramics