|About this Abstract
||2022 TMS Annual Meeting & Exhibition
||Ultrafine-grained and Heterostructured Materials (UFGH XII)
||Deformation Band-Induced Microstructural Evolution during High Pressure Torsion of a Magnesium-Yttrium Alloy
||Christian Roach, Bharat Gwalani, Kiran Solanki, Arun Devaraj, Suveen Mathaudhu
|On-Site Speaker (Planned)
Increasing the strength and low temperature formability of magnesium alloys has recently been accomplished via severe plastic deformation methods that refine the grains to the micrometer-scale or below. High-pressure torsion has been particularly effective given its ability to severely strain the materials under large hydrostatic pressures, which hinders conventional Mg failure modes. Refinement has largely been reported to occur via dynamic recrystallization or progressive “necklacing”, with microstructural saturation being inferred to occur once hardness plateaus. We report our findings on a Mg-3wt%Y alloy processed via HPT with variable pressures and strain levels (number of rotations). Microstructural refinement is observed to occur via increased local strain in intersecting deformation bands (twin or shear bands), and increased refinement is observed to occur past hardness saturation due to further microstructural evolution. These results indicate the variability of refinement mechanisms in Mg alloys and improve our understanding of the pathways to ultrafine grained microstructures.
||Magnesium, Characterization, Mechanical Properties