Towards resolving the anonymity of pyramidal slip in magnesium
نویسندگان
چکیده
Plasticity in magnesium crystals oriented for c-axis compression has been usually attributed to 〈cþa〉 dislocation slip on second-order pyramidal {112̄2} planes. Through molecular dynamics simulations, we investigated the formation and slip characteristics of 〈cþa〉 dislocations on second-order pyramidal planes. It is shown that the critical c-axis compressive stress for these dislocations is almost seven times that for 〈cþa〉 dislocations on first-order pyramidal {101̄1} planes. In particular, it is concluded that firstorder pyramidal near-screw 〈cþa〉 dislocations play a predominant role during the c-axis compression of magnesium crystals. Careful reexaminations of published experimental observations show good agreements with the current predictions. & 2015 Elsevier B.V. All rights reserved.
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