| About this Abstract |
| Meeting |
2012 TMS Annual Meeting & Exhibition
|
| Symposium
|
Magnesium Technology 2012
|
| Presentation Title |
Structural Origin of Reversible Twinning, Non-Schmid Effect, Incoherent Twin Boundaries and Texture of Hexagonal Close-Packed Metals |
| Author(s) |
Bin Li, Xiyan Zhang, Haitham El Kadiri, Suveen Mathaudhu, Quancang Ma |
| On-Site Speaker (Planned) |
Bin Li |
| Abstract Scope |
Profuse {10-12}<10-1-1> extension twinning occurs in Magnesium and other HCP metals during plastic deformation. This twinning mode presents abnormal properties such as reversibility, i.e., upon unloading or removal of external load, twins may shrink or disappear, giving rise to the pseudoelasticity. The {10-12}<10-1-1> twinning may also violate the Schmid Law which applies to all dislocation controlled deformations. The twin boundaries of the {10-12}<10-1-1> twinning may significantly deviate from the {10-12} twinning plane, at odds with twinning theory that requires twinning dislocations glide strictly on the twinning plane. HCP metals also present strong propensity of texture during thermomechanical processing such as extrusion, rolling or severe plastic deformation (SPD). We show that these properties of HCP metals can be well understood from the perspective of atomic shuffling that dominates the deformation twinning. EBSD, TEM and HRTEM observations will be presented to support our conclusions. |
| Proceedings Inclusion? |
Definite: A combination print-CD volume |