Grain Growth Behaviors in a Friction-Stir-Welded ZK60 Magnesium Alloy

Abstract

Grain growth during annealing of a friction-stir-welded (FSWed) ZK60 magnesium alloy has been investigated. We have found that (1) thermal stability exhibited in different parts of stirred zone (SZ) was very different, (2) grain growth was fairly abnormal, and (3) grain growth was directional and shapes of developed grains resembled flow patterns inherent to FSWed structure. We have shown that all peculiarities of the grain growth behaviors can be explained in terms of heterogeneous distribution of second phase particles resulted from FSW.