Deformation-twin-induced grain boundary failure

doi:10.1016/j.scriptamat.2011.10.021

Scripta Materialia

Volume 66, Issue 2, January 2012, Pages 117-120

https://doi.org/10.1016/j.scriptamat.2011.10.021 Get rights and content

This work presents a mechanism of deformation-twin-induced grain boundary failure, and demonstrates the mechanism using molecular dynamics simulations. Deformation twinning is observed as the dominant mechanism during tensile deformation of 〈1 1 0〉 columnar nanocrystalline body-centered cubic Mo. As a twin approaches a grain boundary, local stress concentration develops due to the incompatible plastic deformations in the two neighboring grains. The magnitude of the stress concentration increases as the twin widens, leading to grain boundary cracking by nucleation and coalescence of microcracks/voids.

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Deformation-twin-induced grain boundary failure

Prog. Mater. Sci.

Acta Mater.

Acta Mater.

Acta Mater.

Mater. Sci. Eng. A

Prog. Mater. Sci.

Acta Mater.

Intermetallics

Intermetallics

Mater. Sci. Eng. A

J. Mech. Phys. Solids

Acta Mater.

Scripta Mater.