Effect of Natural Ageing on Precipitation of Al-Zn-Mg-Cu-Li Alloys
Effect of natural ageing on the precipitation of Al-5.6Zn-1.9Mg-1.6Cu- 1.1Li-0.24Cr (in wt.%) alloys were investigated. The ageing processes, microstructure and hardness of the alloys were investigated by Vickers hardness and transmission electron microscopy (TEM). The results show that natural ageing makes the exothermic temperature range of the Al-Zn-Mg-Cu-Li alloys to shift to lower temperature. Natural ageing for 48h and followed by ageing at 120 , precipitates in the matrix of Al-Zn-Mg-Cu-Li alloys are sparse, which lowers the age hardness of the Al-Zn-Mg-Cu-Li alloys.
Z. K. Zhao et al., "Effect of Natural Ageing on Precipitation of Al-Zn-Mg-Cu-Li Alloys", Advanced Materials Research, Vols. 168-170, pp. 2503-2506, 2011