Phase diagram of the PdTe system

• Published in: Journal of the less-common metals 1986-09, Vol.123 (1), p.251-266
• Main Authors: Chattopadhyay, G., Bhatt, Y.J., Khera, S.K.
• Format: Article
• Language: English
• Subjects: Applied sciences; Condensed matter: structure, mechanical and thermal properties; Cross-disciplinary physics: materials science; rheology; Equations of state, phase equilibria, and phase transitions; Exact sciences and technology; Materials science; Metals, semimetals and alloys; Metals. Metallurgy; Phase diagrams and microstructures developed by solidification and solid-solid phase transformations; Phase diagrams of metals and alloys; Physics; Specific materials; Specific phase transitions
• ISSN: 0022-5088
• DOI: 10.1016/0022-5088(86)90134-7

The phase diagram of the PdTe system has been investigated by differential thermal analysis, spot technique, X-ray diffraction and electron probe microanalysis in the composition range 0–50 at.% Te. The resultant phase diagram shows nine crystalline phases and eleven invariant reactions in this composition range. These phases are α (terminal solid solution of tellurium in palladium), β (Pd 9Te 2), γ (Pd 3Te), δ, ϵ (Pd 3Te 2), PdTe, γ′, δ′ and δ″. The last three are high temperature phases reported for the first time in this work. The α phase shows retrograde solid solubility, the maximum being at 12.5 at.% Te. The δ″ phase melts congruently at 905 °C and 27.2 at.% Te. The phases β, γ and δ decompose peritectoidally at 770, 754 and 500 °C; γ′, δ″ and δ′ decompose eutectoidally at 727, 563 and 474 °C and γ′, δ′ and ϵ decompose peritectically at 785, 610 and 507 °C respectively. Thus γ′ and δ′ phases have an upper as well as a lower temperature limit of stability. Two eutectic reactions at 780 and 505 °C occur at 22.5 and 37 at.% Te respectively.