Effect of precipitation on elastic modulus of Al-Zn-Mg-Cu-Li alloys
(1.山东省济南市山东建筑大学材料科学与工程学院
2.School of Materials Science and Engineering, Beijing University of Aeronautics and Astronautics,Beijing 100083, China
3.School of Materials Science and Engineering, Shandong Jianzhu University, Jinan 250101, China)
2.School of Materials Science and Engineering, Beijing University of Aeronautics and Astronautics,Beijing 100083, China
3.School of Materials Science and Engineering, Shandong Jianzhu University, Jinan 250101, China)
Abstract: Al-5.6Zn-3.0Mg-1.6Cu-1.1Li-0.24Cr alloys and Al-8.0Zn-2.4Mg-2.4Cu-1.1Li-0.18Zr alloys (mass fraction, %) were aged by different processes. The microstructure and mechanical properties were determined by transmission electron microscopy(TEM), tensile test and Vicker’s hardness test. The experimental results show that the most signified hardening is obtained by double-ageing or multi-ageing for the Al-Zn-Mg-Cu-Li alloys. The yield strength and the elastic modulus of the Li-containing alloys have relationships with ageing processes. The elastic modulus of Li-containing alloys decreases with the increment of precipitates though it is higher than that of Al-Zn-Mg-Cu alloy.
Key words: Al-Zn-Mg-Cu-Li alloys; ageing; precipitates; elastic modulus; yield strength