Isothermal Section of Al-Si-Ce Ternary System at 1073 K

The phase equilibria in the Al-Si-Ce ternary system at 1073 K is investigated by means of x-ray diffraction and scanning electron microscope coupled with energy dispersive spectroscopy. There exist 12 three-phase regions exist in this system and one can be deduced. One ternary compound T (Ce(AlxSi1−x)2) found in the isothermal section at 1073 K has the LaPtSi structure with a lattice parameter a = 0.4242 nm which composition span ranges from 32.1-47.8 at.%Al, 17.9-33.7 at.% Si, 33.4-34.0 at.% Ce. The maximum solubility of Al (in at.%) in CeSi2−α, CeSi, Ce5Si4, Ce3Si2 and Ce5Si3 at 1073 K is 29.3, 23.8, 2.8, 13.6 and 6.5 respectively, and the maximum solubility of Si (in at.%) in Al4Ce, Al3Ce, Al2Ce and AlCe at 1073 K is 1.4, 1.7, 1.8 and 2.1 respectively.