The solidification paths of Al-Zn-Mg-Cu alloys and its precipitation behavior are analyzed using
software package JMatPro 6.0 for material property simulation of Al-base alloys. The microstructures of the
experimental alloys are analyzed; the experimental results of microstructural analysis are in agreement with the
thermodynamic prediction. Through orthogonal experimental method, this paper designs the composition of
Al-Zn-Mg-Cu alloys by studying the variation of η (MgZn2) phase, S (Al2CuMg) phase, T (AlZnMgCu) phase
amount and precipitation temperatures with different Zn, Mg and Cu contents. It is found that with the optimum
mass fraction of Zn of 6.7%, Mg of 2.2%—2.5% and Cu of 1.6%—2.0%, the mass fraction of η phase can be up to
8.7%—9.22% and that of S phase and T phase can be lower than 0.5%.
YU Jing-jing (于晶晶), LI Xiao-mei (李晓梅), YU Xin-quan (余新泉)
. Thermodynamic Analyse on Equilibrium Precipitation Phases and
Composition Design of Al-Zn-Mg-Cu Alloys[J]. Journal of Shanghai Jiaotong University(Science), 2012
, 17(3)
: 286
-290
.
DOI: 10.1007/s12204-012-1270-4
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