Experimental investigation of phase equilibria in the Cu-Ni-Si ternary system

The phase equilibria in the Cu-Ni-Si ternary system have been investigated experimentally by means of electron probe microanalysis (EPMA), X-ray diffraction (XRD) and differential scanning calorimetry (DSC) analysis on equilibrated ternary alloys. Three isothermal sections at 1073, 1173 and 1273 K are determined in the whole composition range. The existence of liquid phase and the ternary compound τ1 is confirmed at 1073 K. The binary γ (Cu5Si), γ (Ni31Si12), δ (Ni2Si) and θ (Ni2Si) phases exhibit a considerable solubility of a third element. In addition, the γ (Cu5Si) and θ (Ni2Si) phases can be stabilized by the addition of Ni and Cu, respectively.