Superplasticity and internal friction in microcrystalline AZ91 and ZK60 magnesium alloys processed by equal-channel angular pressing

Low-temperature superplasticity (LTSP) and internal friction in microcrystalline ZK60 and AZ91 magnesium alloys processed by equal-channel angular pressing (ECAP) are reported. Excellent low-temperature superplasticity (<300degreesC) was observed in ECAP-processed materials: elongations to failure are 810 and 570% in ZK60 and AZ91 alloys, respectively, at a strain rate of 3 x 10(-3) S-1. Internal friction can be practically used to determine the optimum temperature for superplasticity. (C) 2004 Elsevier B.V. All rights reserved.