Yield strength prediction of rolled Al−(1.44−12.40)Si−0.7Mg alloy sheets under T4 condition

Abstract The effects of Si content on the microstructure and yield strength of Al−(1.44−12.40)Si−0.7Mg (wt.%) alloy sheets under the T4 condition were systematically studied via laser scanning confocal microscopy (LSCM), DSC, TEM and tensile tests. The results show that the recrystallization grain of the alloy sheets becomes more refined with an increase in Si content. When the Si content increases from 1.44 to 12.4 wt.%, the grain size of the alloy sheets decreases from approximately 47 to 10 μm. Further, with an increase in Si content, the volume fraction of the GP zones in the matrix increases slightly. Based on the existing model, a yield strength model for alloy sheets was proposed. The predicted results are in good agreement with the actual experimental results and reveal the strengthening mechanisms of the Al−(1.44−12.40)Si−0.7Mg alloy sheets under the T4 condition and how they are influenced by the Si content.