摘要
The microstructure and mechanical properties of Mg–6Zn–1Y and Mg–6Zn–3Y（wt%） alloys under different cooling rates were investigated. The results show that the second dendrite arm spacing（SDAS） of Mg–6Zn–1Y and Mg–6Zn–3Y is reduced by 32 and 30% with increasing cooling rates（Rc） from 10.2 to 23 K/s, which can be predicted using a empirical model of SDAS=68 R 0：45：45cand SDAS=73 R 0c, respectively. The compressive strength of both alloys increases with increasing the cooling rate, which is attributed to the increase of volume fraction（Vf） of secondary phases under high cooling rate. The interaction of the cooling rate and component with SDAS has been theoretically analyzed using interdependence theory.
The microstructure and mechanical properties of Mg–6Zn–1Y and Mg–6Zn–3Y（wt%） alloys under different cooling rates were investigated. The results show that the second dendrite arm spacing（SDAS） of Mg–6Zn–1Y and Mg–6Zn–3Y is reduced by 32 and 30% with increasing cooling rates（Rc） from 10.2 to 23 K/s, which can be predicted using a empirical model of SDAS=68 R 0：45：45cand SDAS=73 R 0c, respectively. The compressive strength of both alloys increases with increasing the cooling rate, which is attributed to the increase of volume fraction（Vf） of secondary phases under high cooling rate. The interaction of the cooling rate and component with SDAS has been theoretically analyzed using interdependence theory.
基金
financially supported by the National Natural Science Foundation of China (NO. 51464034)
the Cooperation and Exchanges of Nanchang City (2012DWHZXCL@JDYTH-001)
the Educational Commission of Jiangxi Province (No. GJJ13069)
the Innovation Fund Designated for Graduate Students of Jiangxi Province (No. YC2013-S027)
the Hong Kong Scholars Program (No. XJ2012025)
the China Post-doctoral Science Foundation funded project (No. 2012T50594, 2014M551866)
the Jiangxi Post-doctoral Science Foundation (No. 2014KY11)
Doctoral Fund of Ministry of Education of China (No. 20113601110008)
