CHANG Xu-qing(常旭青)1,2,3, MA Tie-hua（马铁华）2,3,4, YANG Yong-biao（杨勇彪）5
(1. Software School, North University of China, Taiyuan 030051, China; 2. Science and Technology on Electronic Test & Measurement Laboratory, North University of China, Taiyuan 030051, China;3. Key Laboratory of Instrumentation Science & Dynamic Measurement（North University of China）, Ministry of Education, Taiyuan 030051, China;4. School of Information and Communication Engineering, North University of China, Taiyuan 030051, China;5. College of Materials Science and Engineering, North University of China, Taiyuan 030051, China)
Abstract： To investigate the dynamic mechanical behavior of AZ31 Mg alloy, dynamic compression was carried out using a split Hopkinson pressure bar (SHPB) apparatus at strain rates up to 2.0×103 s-1 , and dynamic hardness was tested employing a dynamic hardness device at room temperature. Microstructural characteristic was analysed by optical microscopy. The dynamic compression results demonstrate that AZ31 Mg alloy exhibits obvious yield phenomena and strain hardening behavior at high strain rates. The basically same curvature of stress-strain curves shows a similar strain hardening rate. The dynamic yield strength changes little, and the peak stress increases with the strain rates. The dynamic hardness test results indicate that the dynamic mechanical properties of AZ31 alloy sheet are anisotropic. The dynamic hardness increases slowly with average strain for the 0° and 45° oriented samples. For the 90° oriented sample, dynamic hardness with strain increases rapidly first and then decreases when the strain is more than 0.14. An examination by optical microscopy after high strain rate deformation reveals the occurrence of twinning, and the twin area percentage escalates with the strain rate increasing.
Key words：AZ31; dynamic test; mechanical behavior; microstructure
CLD number： TG146.22 Document code： A
Article ID： 1674-8042(2013)02-0194-05doi： 10.3969/j.issn.1674-8042.2013.02.022
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