Phase equilibrium in the vicinity of the Al–Ni–Ru decagonal phase

The Al-rich part of the Al–Ni–Ru phase diagram was re-investigated with respect to the existence of stable quasicrystalline phases. The thermodynamic stability of the ternary decagonal phase with a 1.6 nm periodicity was confirmed in a small compositional range around Al73.1Ni15.7Ru11.2 and at temperatures below 1050 °C. The partial 900 °C isothermal section of Al–Ni–Ru is presented. Apart from the decagonal phase, two ternary crystalline compounds are stable at this temperature. The results are compared to those in Al–Ni–Fe.