Correlation of plastic deformation and dynamic recrystallization in magnesium alloy Zk60

The mechanisms of plastic deformation and dynamic recrystallization (DRX) in a Mg-5.8% Zn-0.65% Zr alloy were studied by compression tests at temperatures between 423 and 723 K and at strain rates ranging From 10(-5) to 10(-1) s(-1). It was shown that the mechanisms of DRX depended on the operating deformation mechanisms which changed with temperature. Low-temperature DRX (LTDRX below 473 K) was associated with the operation of twinning, basal slip and (a+c) dislocation glide. In the intermediate temperature range (473-523 K) continuous DRX (CDRX) was observed and associated with extensive cross-slip due to the Friedel-Escaig mechanism. At temperatures ranging from 573 to 723 K bath bulging of original grain boundaries and subgrain growth were the operating DRX mechanisms and controlled by dislocation climb. (C) 2001 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights reserved.