Mater. Lett.

2021, 292, 129626

We investigate the deformation dynamics in pre-twinned Mg-3Al-1Zn alloy under uniaxial compression based on in situ synchrotron X-ray diagnostics. Stress-strain curves, strain field mapping and X-ray diffraction are achieved simultaneously. The same measurements are conducted on the as-received Mg alloy for comparison. Massive {10 (1) over bar2}-{10 (1) over bar2} double twinning is observed in preexisting twins of the pre-twinned specimen, and abundant {10 (1) over bar2} extension twins are activated in the as-received specimen. The {10 (1) over bar2} extension twinning in the as-received specimen can rapidly boost strain hardening rate by slowing down the process of strain localization. The {10 ($) over bar2}-{10 (1) over bar2} double twinning does not lead to significant reduction in the rate of strain localization, and thus the corresponding increase in strain hardening rate is modest. (C) 2021 Elsevier B.V. All rights reserved.