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Low-energy, Mobile Grain Boundaries in Magnesium.

ABSTRACT: The strong basal texture that is commonly developed during the rolling of magnesium alloy and can even increase during annealing motivates atomic-level study of dislocation structures of both <0001> tilt and twist grain boundaries (GBs) in Magnesium. Both symmetrical tilt and twist GBs over the entire range of rotation angles ? between 0° and 60° are found to have an ordered atomic structure and can be described with grain boundary dislocation models. In particular, 30° tilt and twist GBs are corresponding to energy minima. The 30° tilt GB is characterized with an array of Shockley partial dislocations bp:-bp on every basal plane and the 30° twist GB is characterized with a stacking faulted structure. More interesting, molecular dynamics simulations explored that both 30° tilt and twist GBs are highly mobile associated with collective glide of Shockley partial dislocations. This could be responsible for the formation of the strong basal texture and a significant number of 30° misorientation GBs in Mg alloy during grain growth.

SUBMITTER: Liu X

PROVIDER: S-EPMC4759561 | biostudies-literature | 2016 Feb

REPOSITORIES: biostudies-literature

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Low-energy, Mobile Grain Boundaries in Magnesium.

Liu Xiangli X Wang Jian J

Scientific reports 20160219

The strong basal texture that is commonly developed during the rolling of magnesium alloy and can even increase during annealing motivates atomic-level study of dislocation structures of both <0001> tilt and twist grain boundaries (GBs) in Magnesium. Both symmetrical tilt and twist GBs over the entire range of rotation angles θ between 0° and 60° are found to have an ordered atomic structure and can be described with grain boundary dislocation models. In particular, 30° tilt and twist GBs are co ...[more]

PMID: 26891595

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