| Abstract Scope |
In magnesium, there are two major twinning modes: {10-12}〈10-11〉 and {10-11}〈10-1-2〉. {11-21}〈11-2-6〉 is only observed rare-earth containing Mg alloys, but no in pure Mg. In this work, using atomistic simulation, we investigate the twinning mechanisms in single crystal Mg under c-axis tension. The results show that, both {10-12} and {11-21} twins are initiated. The {11-21} twin grows slowly and eventually gets consumed by the {10-12} twin as the tensile strain increases. This indicates that the interface between the {10-12} and {11-21} twins is mobile. By performing lattice correspondence analysis, we show that the {11-22}, {11-20} and {10-10} are corresponding planes of {10-12}〈10-11〉 and {11-21}〈11-2-6〉 twinning modes. Thus, the interface between the {10-12} and {11-21} twins, which roughly falls between the corresponding planes, is mobile, allowing the {10-12} twin to consume the {11-21} twin. This well explains why {11-21} twins are rarely observed in Mg and Mg alloys. |