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Indexed by:期刊论文

Date of Publication:2016-12-11

Journal:MATERIALS SCIENCE AND TECHNOLOGY

Included Journals:SCIE、EI、Scopus

Volume:32

Issue:18

Page Number:1869-1876

ISSN No.:0267-0836

Key Words:Multi-pass; Dynamic recrystallisation; Grain refinement; Fracture mode; Large strain rolling

Abstract:As-cast AZ31 magnesium alloy subjected to multi-pass large strain rolling was investigated. A successive rolling process up to three passes was carried out at 370 degrees C with a pass reduction of 30%. Deformation microstructure characteristics prove that the dynamic recrystallisation (DRX) mode changed with the increase of rolling passes. In the first pass, DRX related to twinning played a dominant role. But in the third pass, DRX grains mainly appeared around the pre-existing grain boundaries. The ultimate strength and elongation of rolled sheets after three passes rolling are enhanced by 37 and 39%, respectively, compared to the as-cast alloy. Meanwhile, the tensile fracture mode was ductile fracture which was different from the ductile-brittle fracture of as-cast.