|About this Abstract
|2022 TMS Annual Meeting & Exhibition
|Ultrafine-grained and Heterostructured Materials (UFGH XII)
|Strength Softening Mitigation in Bimodal Nanostructured Metals
|Han Wang, Penghui Cao
|On-Site Speaker (Planned)
Conventional metals with homogenous grain size experience strength softening with decreasing grain size to dozen nanometers. In this work, we reveal that the softening rate can be controlled by tailoring structural heterogeneity. By increasing the size ratio of large and small grains in a bimodal structured metal, we find the softening rate in the inverse Hall-Petch regime is considerably lowered, and this softening mitigation is mediated by nucleation and storage of extended dislocations in large grains. Consequently, the bimodal structured systems exhibit a smaller strain rate sensitivity as compared to their homogeneous counterparts. These findings shed light on the deformation mechanisms underlying extraordinary mechanical behaviors of materials with structural heterogeneity.
|Modeling and Simulation, Mechanical Properties, Computational Materials Science & Engineering