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Indexed by:期刊论文

Date of Publication:2008-12-01

Journal:TRANSACTIONS OF NONFERROUS METALS SOCIETY OF CHINA

Included Journals:SCIE、EI、ISTIC、Scopus

Volume:18

Issue:SPEC. ISSUE 1

Page Number:S86-S90

ISSN No.:1003-6326

Key Words:sub-rapid solidification; grain size; mechanical property; fracture surface morphology

Abstract:The microstructure of sub-rapid solidification processed AZ61A magnesium alloy was presented and discussed. The results show that the grain size of the foil is significantly refined, and the grain morphology is cellular or globular. The eutectic transformation L ->alpha-Mg+beta-Mg(17)Al(12) and microsegregation in conventionally solidified AZ61A alloy are suppressed to a great extent. The beta-Mg(17)Al(12) phases located in the alpha-Mg grain boundaries are largely decreased due to high solidification cooling rate. As a consequence, the alloying elements Al, Zn, Mn show much higher solid solubility and the sub-rapid solidification microstructure dominantly consists of supersaturated alpha-Mg solid solution. The mechanical proper-ties and fractographic analysis reveal that the fracture mechanism and corresponding morphology of the rapture surface of tensile bars are linked to the microstructure obtained and depend on the sub-solidification processes.