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The precipitation behavior of a pretwinned Mg–6Al–1Zn alloy and the effect on subsequent deformation

Published online by Cambridge University Press:  12 September 2014

Yin Zhang
Affiliation:
College of Materials Science and Engineering, Chongqing University, Chongqing 400044, People's Republic of China; and National Engineering Research Center for Mg Alloys, Chongqing University, Chongqing 400044, People's Republic of China
Tianmo Liu*
Affiliation:
College of Materials Science and Engineering, Chongqing University, Chongqing 400044, People's Republic of China; and National Engineering Research Center for Mg Alloys, Chongqing University, Chongqing 400044, People's Republic of China
Xuezheng Ding
Affiliation:
College of Materials Science and Engineering, Chongqing University, Chongqing 400044, People's Republic of China; and National Engineering Research Center for Mg Alloys, Chongqing University, Chongqing 400044, People's Republic of China
Shun Xu
Affiliation:
College of Materials Science and Engineering, Chongqing University, Chongqing 400044, People's Republic of China; and National Engineering Research Center for Mg Alloys, Chongqing University, Chongqing 400044, People's Republic of China
Jiejun He
Affiliation:
College of Materials Science and Engineering, Chongqing University, Chongqing 400044, People's Republic of China; and National Engineering Research Center for Mg Alloys, Chongqing University, Chongqing 400044, People's Republic of China
Hongbing Chen
Affiliation:
College of Materials Science and Engineering, Chongqing University, Chongqing 400044, People's Republic of China; and National Engineering Research Center for Mg Alloys, Chongqing University, Chongqing 400044, People's Republic of China
Fusheng Pan
Affiliation:
College of Materials Science and Engineering, Chongqing University, Chongqing 400044, People's Republic of China; and National Engineering Research Center for Mg Alloys, Chongqing University, Chongqing 400044, People's Republic of China
Liwei Lu*
Affiliation:
College of Electromechanical Engineering, Hunan University of Science and Technology, Xiangtan 411201, China
*
a)Address all correspondence to these authors. e-mail: tmliu@cqu.edu.cn
b)e-mail: llwcqu@163.com
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Abstract

In this study, the precipitation behavior of the pretwinned extruded Mg–6Al–1Zn alloy was investigated. It was observed that the precipitates preferentially nucleated at the twin boundaries or within the preexistent twins. This distribution of the precipitates led to the distinguishing influences on subsequent compression and tension process, which were dominated by twinning and detwinning of the preexistent twins, respectively. The compressive yield strength after aging was a little lower than the stress when the precompression was interrupted, which meant that the impeding effect of precipitation on twin expansion was relatively smaller than that of dislocations induced by precompression. However, the tensile yield strength of aged samples was extremely higher than that of non-aged samples as the migration of the twin boundaries during detwinning was considerably hindered because of the preferential precipitation within the preexistent {10-12} twins.

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Articles
Copyright
Copyright © Materials Research Society 2014 

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References

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