Phase Equilibria in Aluminium-Ruthenium-Silicon System near 1200 Kelvin

A narrow-gap semiconductor with a complex crystal structure was recently discovered in the Al-Ru-Si system. To determine the homogeneity range of the semiconductor phase and further discover new phases, phase equilibria in the Al-Ru-Si system near 1200 K were investigated through prolonged-annealing experiments. Eleven new ternary phases including two incommensurate composite-crystalline and an icosahedral quasicrystalline phases were identified using powder and single-crystal X-ray diffraction, and their compositions at two-phase and three-phase equilibria were evaluated by means of electron-probe X-ray microanalysis. On the basis of the data obtained in this study and those adopted from the literature, a tentative isothermal section of the Al-Ru-Si equilibrium phase diagram near 1200 K was drawn. [doi:10.2320/matertrans.MT-M2023128]