Refinement of the Al-rich part of the Al–Cu–Re phase diagram and atomic model of the ternary Al_6.2Cu₂Re phase

Partial isothermal sections at 800, 650 and 590 °C were constructed for an Al-rich compositional range of Al–Cu–Re. The maximal solubility of Cu in the Al₁₁Re₄, h-Al₄Re and l-Al₄Re phases was found to be ∼6, 4.5, and 2.3 at% respectively, while the solubility of Re in the Al–Cu θ, η₁and ε₂phases was below 0.5 at%. Below 740 °C, a ternary hexagonal phase (P6₃, a = 1.1029 and c = 1.2746 nm) is formed in a small compositional range close to Al₆₅Cu₂₅Re₁₀. Its structural model was deduced by direct methods applied on the precession electron diffraction tomography data.