Correlation of plastic deformation and dynamic recrystallization in magnesium alloy Zk60

The mechanisms of plastic deformation and dynamic recrystallization (DRX) i n a Mg-5.8% Zn-0.65% Zr alloy were studied by compression tests at temperat ures 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 sl ip and (a+c) dislocation glide. In the intermediate temperature range (473- 523 K) continuous DRX (CDRX) was observed and associated with extensive cro ss-slip due to the Friedel-Escaig mechanism. At temperatures ranging from 5 73 to 723 K bath bulging of original grain boundaries and subgrain growth w ere the operating DRX mechanisms and controlled by dislocation climb. (C) 2 001 Acta Materialia Inc. Published by Elsevier Science Ltd. All rights rese rved.