|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Ultrafine-grained Materials X
||Severe Deformation at Elevated Temperatures - the Key to Extremely Elongated Nanostructures
||Oliver Renk, Pradipta Ghosh, Reinhard Pippan
|On-Site Speaker (Planned)
The increased strength of nanostructured materials generally decreases their ductility or fracture toughness. Recent studies suggest that materials consisting of grains with high aspect ratios could be the link to materials combining exceptional strength and damage tolerance. However, synthesizing metals by Severe Plastic Deformation produces only aspect ratios of 2 – 4, a consequence of structural restoration occurring during deformation. It is commonly accepted that these processes take place more frequently at elevated temperatures, leading to further reduced aspect ratios.
We show for a variety of metals that this only holds true above a critical temperature. Up to this temperature, the aspect ratio continuously increases. This offers the possibility to selectively process extremely elongated structures, what may be the key to overcome the strength-toughness trade off. Reasons leading to this unexpected behaviour as well as the influence of the material, processing route or alloying will be the center of discussion.
||Planned: Supplemental Proceedings volume