Alloy Constitution and Phase Equilibria in the Hf-Ru-Rh System. I. Solidus Surface of the Partial Hf–HfRu–HfRh System

• Published in: Powder metallurgy and metal ceramics 2016-01, Vol.54 (9-10), p.568-582
• Main Authors: Kryklya, L. S., Kornienko, K. E., Khoruzhaya, V. G., Petyukh, V. M., Duma, L. A., Sobolev, V. B.
• Format: Article
• Language: English
• Subjects: Binary system; Binary systems; Ceramics; Characterization and Evaluation of Materials; Chemistry and Materials Science; Composites; Constitution; Equilibrium; Glass; Hafnium; Hafnium base alloys; Materials Science; Metallic Materials; Natural Materials; Phase equilibria; Physicochemical Materials Research; Powder metallurgy; Solid solutions; Solidus; Systems (metallurgical); Ternary systems; Triangles; Triangulation
• ISSN: 1068-1302; 1573-9066
• DOI: 10.1007/s11106-016-9750-y

The data obtained by physicochemical analysis techniques are used for the first time to determine the nature of phase equilibria in the Hf–Ru–Rh system at 50−100 at.% Hf (Hf–HfRu–HfRh partial system) at subsolidus temperatures and to construct the solidus surface on the composition triangle. It is established that there is a continuous series of solid solutions between isostructural (CsCl type) HfRu-based and high-temperature δ-HfRh phases. This allowed triangulation of the Hf–Ru–Rh system into two partial ones at 50 at.% Hf. The β-Hf solid solution, γ-Hf 2 Rh phase (Ti 2 Ni structure), and δ-phase, forming three single-phase regions on the solidus surface, participate in the phase equilibria at subsolidus temperatures. The ruled surfaces formed by the δ and δγ tie lines decrease from the bounding binary systems to theδ γ isothermal plane at 1373°C and the γ ruled surface decreases in turn to the Hf–Rh binary system.