Effect of strain rate and temperature on fracture of magnesium alloy AZ31B

The fracture behavior of twin roll cast AZ31B magnesium has been studied in tension. Explored ranges of temperature and strain rate were wide enough to encompass noticeable transitions in fracture characteristics at both macroscopic and microscopic scales. Overall properties include strain rate sensitivity, thermal softening, strain to failure, failure mode, plastic anisotropy and work of fracture. The micro mechanisms of damage initiation and accumulation were inferred from tests interrupted at incipient macrocrack formation for key test conditions. The competing roles of voids nucleated on aligned inclusion clusters and at presumed contraction double twins are discussed. (C) 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.