B. Grushko and M. Yurechko

Phase equilibrium was studied in Al-rich Al-Rh and Al-Cu-Rh alloys. We present a partial Al-Rh phase diagram. In addition to previously reported Al-Rh phases, two complicated orthorhombic compounds were found close to the A13Rh composition. Partial 900 and 800°C isothermal sections of the AI-Cu-Rh phase diagram were studied in the vicinity of the decagonal phase. At these temperatures the stable decagonal phase was found to be the only ternary compound. It is in equilibrium with the ternary extensions of three binary Al-Rh phases and at 900°C also with the liquid.