The mechanisms of plastic deformation and dynamic recrystallization (DRX) in a Mg-5.8 percent Zn-0.65 percent 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 both bulging of original grain boundaries and subgrain growth were the operating DRX mechanisms and controlled by dislocation climb.
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