ISSN: 1003-6326
CN: 43-1239/TG
CODEN: TNMCEW

Vol. 18    Special 1    December 2008

[PDF]    
Influence of sub-rapid solidification on microstructure and mechanical properties of AZ61A magnesium alloy
TENG Hai-tao(滕海涛), LI Ting-ju(李廷举), ZHANG Xiao-li(张小立), ZHANG Zhong-tao(张忠涛)
(State Key Laboratory of Materials Modification, School of Materials Science and Engineering, Dalian University of Technology, Dalian 116024, China)
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→α-Mg+β-Mg17Al12 and microsegregation in conventionally solidified AZ61A alloy are suppressed to a great extent. The β-Mg17Al12 phases located in the α-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 α-Mg solid solution. The mechanical properties 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.
Key words: sub-rapid solidification; grain size; mechanical property; fracture surface morphology
Superintended by The China Association for Science and Technology (CAST)
Sponsored by The Nonferrous Metals Society of China (NFSOC)
Managed by Central South University (CSU) 湘ICP备09001153号-9