Influence of stress states on superplastic deformation behavior in a Zn-Al eutectoid alloy

Abstract

A Zn-Al eutectoid alloy known as a fine-grained superplastic material is tested in tension and compression under superplastic conditions, and the influence of the stress state on superplastic deformation behavior, such as flow stress, is investigated. In the compression test, deformation is interrupted and turning is performed to remove a barreled portion so that the specimen section becomes uniform, and them the deformation is continued. As a result, flow stress in the compression becomes higher than that in tension even after the barreled portion is removed. Microstructural change during the deformation is also investigated.