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Indexed by:期刊论文

Date of Publication:2009-06-01

Journal:MATERIALS CHARACTERIZATION

Included Journals:SCIE、EI

Volume:60

Issue:6

Page Number:482-486

ISSN No.:1044-5803

Key Words:Magnesium alloy; Sub-rapid solidification; Microstructure; Microdistribution

Abstract:AZ61 magnesium alloy foils of 0.5-3.0 mm thick were successfully produced by using sub-rapid solidification technique. Microstructures of conventionally solidified (CS) and sub-rapidly solidified (sub-RS) alloys were examined by optical microscope (OM) and scanning electron microscope (SEM). The results showed that the cellular grain of 1.8-13.5 mu m can be obtained during sub-rapid solidification process. Phase compositions and microdistribution of the alloying elements in the foils were analyzed by X-ray diffraction (XRD) and electron probe microanalyzer (EPMA), respectively. The eutectic transformation L ->alpha-Mg+beta-Mg(17)Al(12) and microsegregation in conventionally solidified AZ61 alloy were remarkably suppressed in sub-rapid solidification process. As a consequence, the alloying elements Al, Zn, Mn showed much higher solid solubility and the sub-rapid solidification microstructures dominantly consisted of supersaturated alpha-Mg solid solution. Meanwhile, the beta-Mg(17)Al(12) phases located in the alpha-Mg grain boundaries are largely decreased due to high solidification cooling rate. (C) 2008 Elsevier Inc. All rights reserved.