Hardening Effects of Precipitates with Different Shapes on the Twinning in Magnesium Alloys
Molecular dynamics (MD) simulations were performed to quantify the effect of the precipitate shape on the interactions with extension twin boundaries in magnesium alloys. Three precipitate shapes, including plate-, cube- and rod-like, were studied. The simulation results indicate that the blocking effect of plate-like precipitate is weakly affected by the precipitate aspect ratio (plate width/plate thickness; so, cube-like precipitate is at aspect ratio of 1), while the rod-like precipitate has a hardening effect decreasing with the increasing aspect ratio (rod length/rod width). This suggests that the plate-like precipitate has an identical hardening effect as the cube-like precipitate and a higher effect than the rod-like precipitate.
KeywordsPrecipitation hardening Molecular dynamics Extension twinning Precipitate shape Magnesium alloys
The financial support from National Natural Science Foundation of China (11672193, U1730106) is acknowledged. HF acknowledges the Alexander von Humboldt fellowship. Author JAE acknowledges support by the US Army Research Laboratory (#W911NF-12-2-0022).
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