|About this Abstract
||2016 TMS Annual Meeting & Exhibition
||Ultrafine Grained Materials IX
||Beneficial and Detrimental Effects of Heat Treatments on the Formability of Ultrafine Grained Steel
||Enrico Bruder, Vanessa Kaune, Anton Hohenwarter, Clemens Müller
|On-Site Speaker (Planned)
A key aspect of severe plastic deformation (SPD) processes is the invariant sample geometry which necessitates subsequent processing steps such as forming to generate the final product shape. Ultrafine grained materials are known for their combination of high strength and ductile behavior, yet they typically lack strain hardening capability which makes them prone to strain localizations. In the present work the effects of heat treatments on the formability of ultrafine grained steels processed by high pressure torsion are investigated. Under uniaxial tension the as processed condition shows a ductile behavior with high post-necking-elongation whereas brittle fracture occurs after a recovery annealing. This is contrary to the behavior under 3-point-bending where brittle shear fracture occurs for the as processed condition and the formability improves significantly after recovery annealing. These results will be discussed with respect to dislocation source hardening effects and damage induced during SPD processing.