Aging Characteristics of 7A52 Al-Zn-Mg Alloy
The influence of aging treatment on microstructure, mechanical and electrical properties of 7A52 alloy was investigated by mechanical property test, electrical conductivity measurement, XRD and TEM analysis. The results showed that the alloy was a typical aging hardening alloy. During aging supersaturated solution decomposed, G.P. zones and η'(MgZn2) precipitated. The precipitates of the alloy aging at 100°C were mainly G.P. zones with the size of about 5nm. During aging at 120°C, η’ precipitates nucleated from the G.P. zones. With increasing aging temperature and time, the size and amount of η' increased. As aged at 120°C for 24h the tensile strength, yield strength, elongation and electrical conductivity of the alloy were 496 MPa, 445 MPa, 9.5% and 26 %IACS, respectively. The G.P. zones and η' dispersion strengthening are the major strengthening mechanisms for the studied alloy at the single-stage peak aging.
Yafang Han et al.
J. W. Huang et al., "Aging Characteristics of 7A52 Al-Zn-Mg Alloy", Materials Science Forum, Vols. 546-549, pp. 867-870, 2007