⟨c plus a⟩ dislocations shearing (0001)α plate precipitates in an Mg-Zn-Mn alloy

Precipitation hardening is an effective way to strengthen Mg alloys as precipitates can reduce the mobility of dislocations. Previous investigations suggest that pyramidal < c + a > dislocations can only bypass precipitates. Here we provide solid atomic resolution evidence that < c + a > dislocations can shear through plate precipitates, leaving behind shear trace lines. The possible shearing process was analyzed based on the crystallographic orientation relationship between the precipitates and the Mg matrix. (C) 2019 Acta Materialia Inc Published by Elsevier Ltd. All rights reserved.