The liquidus surface projection of the scandium-ruthenium-rhodium system in the field of compositions 0–50 at.% Sc

Abstract

The projection of the liquidus surface of the ScRuRh system (in the field of compositions 0–50 at.% Sc) on the concentrational triangle is plotted using metallography, X-ray diffraction, microprobe and differential thermal analysis data. It has been established, that ternary compounds do not form in the system. Its liquidus surface consists of five surfaces of primary crystallization of ruthenium and rhodium solid solutions as well as of the phases based on ScRu 2, ScRh 3 and the δ phase (a continuous series of solid solutions between isostructural CsCl-type structure phases based on ScRu and ScRh). The highest temperature on the surface is 2334 °C, which corresponds to the melting of pure ruthenium; the lowest temperature is 1520 °C (of the existence of ternary eutectic L F 1 ⇄ δ + 〈ScRh 3〉 + 〈Ru〉).