Phase diagrams of Ln-Ba-Cu-O systems (Ln = lanthanide)
Description
The formation of solid phases in the Ln-Ba-Cu-O system (Ln=lanthanide) and their stability have been investigated. At temperatures above 1173 K, mainly four quaternary oxides exist in air: LnBa2Cu3O7-x (Ln123), Ln2BaCuO5 (Ln211), LnBa6Cu3Ox (Ln163) and LnBa4Cu3Ox (Ln143). A systematic study clarified that there is a size limit for the Ln3+ to form quaternary oxides, beyond which the phase stability decreases or changes to another crystal structure. The 123 phase in the Yb system was found to be not stable at low temperatures under a high oxygen partial pressure. The solid solution of quaternary oxides is formed when the radius of Ln3+ ion is large. Several phase diagrams of Ln-Ba-Cu-O system with Ln=Yb, Ho, Y, Nd and Pr have been made clear. (orig.)
Additional details
Publishing Information
- Journal Title
- Zeitschrift fuer Metallkunde
- Journal Volume
- 84
- Journal Issue
- 8
- Journal Page Range
- p. 522-528.
- ISSN
- 0044-3093
- CODEN
- ZEMTAE
INIS
- Country of Publication
- Germany
- Country of Input or Organization
- Germany
- INIS RN
- 25002233
- Subject category
- S36: MATERIALS SCIENCE;
- Descriptors DEI
- BARIUM OXIDES; COPPER OXIDES; HIGH-TC SUPERCONDUCTORS; HOLMIUM OXIDES; NEODYMIUM OXIDES; PHASE DIAGRAMS; PRASEODYMIUM OXIDES; RARE EARTH COMPOUNDS; YTTERBIUM OXIDES
- Descriptors DEC
- ALKALINE EARTH METAL COMPOUNDS; BARIUM COMPOUNDS; CHALCOGENIDES; COPPER COMPOUNDS; DIAGRAMS; HOLMIUM COMPOUNDS; INFORMATION; NEODYMIUM COMPOUNDS; OXIDES; OXYGEN COMPOUNDS; PRASEODYMIUM COMPOUNDS; SUPERCONDUCTORS; TRANSITION ELEMENT COMPOUNDS; YTTERBIUM COMPOUNDS