|About this Abstract
||2018 TMS Annual Meeting & Exhibition
||Ultrafine-grained Materials X
||Evolution of Structural Instabilities during Cyclic Deformation of UFG Metals
||Marlene Kapp, Oliver Renk, Thomas Leitner, Pradipta Ghosh, Bo Yang, Reinhard Pippan
|On-Site Speaker (Planned)
In the course of low cycle fatigue of ultrafine-grained metals two phenomena destabilizing the structure can occur, which are the formation of shear bands and grain growth. Cyclic high pressure torsion experiments offer the unique possibility to study their evolution up to large cyclic strains as the hydrostatic pressure prevents failure of the sample. It will be shown, that grains grow in an accelerated fashion within the shear band region at room temperature but also under cryogenic conditions. The observation of intensified grain growth with increasing strain amplitudes and accumulated strains allows for distinct conclusions about driving forces for cyclically induced grain growth. The evolution of preferential torsional texture components from electron back scatter diffraction data points out to the important role of dislocation based plasticity during the coarsening procedure. Finally, the absence of sample damage allows to quantify the softening portion solely stemming from grain coarsening.
||Planned: Supplemental Proceedings volume