The role of back stress caused by precipitates on {10121} twinning in a Mg-6Zn alloy

In the present study, the effect of precipitate characteristics on {1012} extension twinning have been studied in a Z6 magnesium alloy. A strongly textured Z6 alloy plate was mechanically tested in twinning dominated orientation in solution treated and aged states. Optical microscopy, transmission electron microscopy (TEM) and visco-plastic self consistent (VPSC) modelling are used to examine the effect of precipitate characteristics on twinning. The yield stress was observed to increase by similar to 80 MPa during ageing and it was estimated that CRSS for twinning increased by similar to 29 MPa based on VPSC simulations. The increment of twin system strengthening can be attributed to back stress generated by elastically deforming particles. (C) 2015 Elsevier B.V. All rights reserved.