|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Ultrafine-grained Materials X
||Averting Plastic Flow Localization in Metal Nanocomposites by Tailoring Microstructure Morphology
||Ian McCue, Mengying Liu, Michael Demkowicz
|On-Site Speaker (Planned)
Nanostructured metals – nanocrystalline polycrystals, nanolaminates and nanocomposites – present significant advantages over conventional bulk metals, such as high strength, radiation-damage tolerance, and fatigue resistance. However, an impediment to their widespread technological use is that they fail with minimal uniform plastic deformation due to plastic flow localization. Here we show that flow localization can be averted by engineering the microstructure morphology in metal nanocomposites via solid metal dealloying. Using this technique we fabricated model materials with different microstructural length scales – from 30 nm to 100 nm – and different composite morphologies. We then evaluated their mechanical behavior using nanoindentation. By examining material extrusion (i.e., pile-up) around the indents, we determined the effect of length scales and morphologies on flow localization. This work identifies microstructure morphologies that are able to strain harden, providing design criteria for nanostructured materials that can undergo uniform, large-scale plastic deformation.
||Planned: Supplemental Proceedings volume