Abstract Scope |
Mg presents low strain to failure in c-axis compression, due to the fact that pyramidal dislocations, aka <c+a> dislocations, are hard to activate. Recent in-situ transmission electron microscopy study revealed that single crystal Mg could present very large plasticity (> 25%) in c-axis compression as a result of activation of high density, mobile <c+a> dislocations. It follows that if alloying elements that are able to lower the energy barrier to activating <c+a> dislocations can be identified, ductile Mg alloys can then be designed and processed. In this talk, we show that these alloying elements can be found by performing first principles high-throughput screening. In this approach, how alloying elements influence the generalized stacking fault energy on the pyramidal planes is calculated. Those elements that are able to reduce the unstable stacking fault energy, i.e. the energy barrier to dislocation nucleation and glide, are identified by combing through the Periodic Table. |