Phase relationships in the Al-rich region of the Al-Cu-Er system

▶ One ternary phase τ1-Al8Cu4Er in Al-rich region with a composition of 59.4-60.4 at.% Al, 32.2-33.8 at.% Cu, and 6.4-7.7 at.% Er is observed in both as-cast and annealed alloys. At 673 K, the binary Al3Er phase dissolves about 3.51 at.% Cu. ▶ The calculated solidification paths (based on the CALPHAD method) of as-cast alloys are in agreement with the experimental results. ▶ It can be found that the resultant thermodynamic database can be applied to case studies of as-cast alloys, showing that the literature thermodynamic description of the Al-Cu-Er system is reliable as a working basis for computer-assisted alloy design.