An investigation of the Al–Pd–Rh phase diagram between 50 and 100 at% Al

Partial 1100, 1000, 900 and 790 °C isothermal sections of the Al–Pd–Rh phase diagram were studied. The isostructural binary AlPd and AlRh phases probably form a continuous β-range of the CsCl-type solid solutions. The Al–Pd and Al–Rh ε-phases form another continuous range. The C–Al5Rh2 phase dissolves up to 13 at% Pd, Al9Rh2 and Al7Rh3 are extended up to 3 at% Pd. Two ternary phases: cubic C2 (a=1.5483 nm) and hexagonal C3 (a=1.09159, c=1.3386 nm) were revealed. The former extends along about 65 at% Al from 4 to 27 at% Pd.