The CaO-SrO-CuO-O-2 system: Phase equilibria and thermodynamic properties at 1123 K


Autoria(s): Jacob, KT; Raj, Markondeya P; Waseda, Y
Data(s)

01/04/1995

Resumo

Phase relationships in the CaO-SrO-CuO system in pure oxygen at 1.01 x 10(5) Pa pressure were determined by equilibrating different compositions at 1123 K for similar to 120 h and analyzing the phases present in the quenched samples using X-ray diffraction (XRD), optical and scanning electron microscopy, and energy dispersive analysis of X-rays (EDAX). Four solid solution series were observed in the system, The CawSr1-wO monoxide solid solution with rock-salt structure was found to exhibit an asymmetric miscibility gap, The mixing properties of the monoxide system were deduced using a subregular solution model, For the (CaxSr1-x)(2)CuO3 series, a complete solid solution range with orthorhombic space group Immm was obtained. Calcium substituted for strontium up to 68 at. % in SrCuO2+delta and 51.5 at. % in Sr14Cu24O41-delta. The tie lines between the solid solutions were determined accurately, The activity-composition relations in (CaxSr1-x)(2)CuO3, CaySr1-yCuO2+delta, and (Ca2Sr1-z)(14)Cu24O41-delta solid solutions were determined from experimental tie lines. Activities in the (CaxSr1-x)(2)CuO3 and CaySr1-yCuO2+delta series were close to the predictions of the Temkin model, The behavior of the (CazSr1-(z))(14)Cu24O41-delta solid solution was more complex, with the activity of SrCu(24/14)O-(41-delta/14) exhibiting both positive and negative deviations from ideality. Gibbs energy of formation of the CaCuO2+delta metastable phase at 1123 K was deduced from an analysis of the phase diagram.

Formato

application/pdf

Identificador

http://eprints.iisc.ernet.in/37955/1/The_CaO-SrO-.pdf

Jacob, KT and Raj, Markondeya P and Waseda, Y (1995) The CaO-SrO-CuO-O-2 system: Phase equilibria and thermodynamic properties at 1123 K. In: Journal of Phase Equilibria, 16 (2). pp. 113-120.

Publicador

ASM International

Relação

http://www.springerlink.com/content/x78h07m574436694/

http://eprints.iisc.ernet.in/37955/

Palavras-Chave #Materials Engineering (formerly Metallurgy)
Tipo

Journal Article

PeerReviewed