Grain size effects on dislocation and twinning mediated plasticity in magnesium

作者：Fan, Haidong^*; Aubry, Sylvie; Arsenlis, Athanasios; El-Awady, Jaafar A.

来源：Scripta Materialia, 2016, 112: 50-53.

DOI：10.1016/j.scriptamat.2015.09.008

• Discrete dislocation dynamics
• Size effects
• Dislocation-twin boundary interactions
• Magnesium
• Twinning plasticity

Grain size effects on the competition between dislocation slip and {10 (1) over bar2}-twinning in magnesium are investigated using discrete dislocation dynamics simulations. These simulations account for dislocation-twin boundary interactions and twin boundary migration through the glide of twinning dislocations. It is shown that twinning deformation exhibits a strong grain size effect; while dislocation mediated slip in untwinned polycrystals displays a weak one. This leads to a critical grain size at 2.7 mu m, above which twinning dominates, and below which dislocation slip dominates.

• 出版日期2016-2
• 单位四川大学