Thermodynamic Calculation of the Liquidus Projections of the Al-Cu-Fe-Mg, Al-Cu-Mg-Si, and Al-Fe-Mg-Si Quaternary Systems on Al-Rich Corner

The thermodynamic calculations of Al-Cu-Fe-Mg, Al-Cu-Mg-Si and Al–Fe–Mg–Si quaternary systems were carried out using CALPHAD method, based on the Al–Cu–Fe–Mg–Si thermodynamic database. The liquidus projection of Al–Cu–Fe–Mg, Al–Cu–Mg–Si and Al–Fe–Mg–Si quaternary systems at Al-rich corner were constructed, and the solidification structures of Al-12Cu-7Mg-1Fe, Al-14Cu-2Mg-4Si, Al-0.3Fe-6Mg-12Si (wt.%) alloys were analyzed by the Scheil solidification simulation. The calculated results agree well with the previous experimental data. The liquidus projections of three quaternary aluminum alloys at the Al-rich corner were accurately plotted, which could be helpful for the analysis of solidification process of multicomponent alloy systems, and provide an important theoretical basis for the material design of aluminum alloys.