LAUSR

Abstract Phase equilibria of the Al Si Zr system were investigated using equilibrated alloys. All alloys were studied by X-ray powder diffraction, scanning electron microscopy and energy dispersive spectroscopy. The ternary phase τ 1 was found at 700 and 900 °C, while the τ 2 phase was only identified at 900 °C. 12 three-phase regions were experimentally determined in isothermal sections of the Al Si Zr system at both 700 and 900 °C. The solubility of Si in the intermediate and solution phases (i.e. Al 3 Zr, Al 2 Zr, Al 3 Zr 2 , AlZr 3 , α-Al and (Zr)) at the Al Zr side is limited, whereas the solubility of Al in the Si Zr intermetallic (except the Si 2 Zr 3 phase) is reverse. In addition, Al in the αSiZr phase at 900 °C decreased to 0.5 at.% from 10.3 at.% at 700 °C.