Experimental and thermodynamic investigation of Al-Cu-Nd ternary system

The phase relationships in the Al-Cu-Nd ternary system at 673 K have been investigated by X-ray powder diffraction (XRD) and scanning electron microscope (SEM) with energy disperse X-ray spectroscopy (EDS) in backscattered electron imaging (BSE) modes. The existence of six ternary Stoichiometric compounds, namely τ1-Al8Cu4Nd, τ2-Al9Cu8Nd2, τ3-Al6Cu7Nd, τ4-Al2.4Cu8.6Nd, τ5-Al3CuNd, τ6-AlCuNd, have been confirmed. A complete thermodynamic description of the Al-Cu-Nd ternary system coupled with the CALPHAD method is obtained based on experimental results and first-principles calculations. The calculated phase equilibria were in agreement with the available experimental data.