Phase Stability and Decomposition of Superconductive (Y1-xCax)Ba2Cu4O8 (0≦x≦0.1)
- 1 June 1990
- journal article
- Published by IOP Publishing in Japanese Journal of Applied Physics
- Vol. 29 (6A), L915
- https://doi.org/10.1143/jjap.29.l915
Abstract
The stability of (Y1-x Ca x )Ba2Cu4O8 has been studied as a function of Ca content, temperature and oxygen partial pressure, P(O2), by means of thermogravimetry and differential thermal analysis. When heated at P(O2)=1 atm, YBa2Cu4O8 decomposed into YBa2Cu3.5O7.5-Y (1-2-3.5) and CuO above 899°C and the resultant 1-2-3.5 phase decomposed into YBa2Cu3O7-z (1-2-3) and CuO above 926°C. As the Ca content increased, the decomposition temperatures of both 1-2-4 and 1-2-3.5 phases were decreased and they tended to merge. Actually, when the Ca content was as high as 10% of the Y content, the 1-2-4 phase decomposed directly into a 1-2-3 phase and CuO at 884°C.Keywords
This publication has 10 references indexed in Scilit:
- Synthesis and properties of the YBa2Cu4O8 superconductorPhysica C: Superconductivity and its Applications, 1990
- Synthesis of 80 K superconducting YBa2Cu4O8 via a novel routePhysica C: Superconductivity and its Applications, 1990
- Calcium-substituted superconducting RBa2Cu4O8 with Tc ∼ 90 K prepared at one atmospherePhysica C: Superconductivity and its Applications, 1990
- Synthesis of B2YCu4O8 by anionic oxidation-reductionJournal of Materials Research, 1989
- Tc increased to 90 K in YBa2Cu408 by Ca dopingNature, 1989
- Eight new high-temperature superconductors with the 1:2:4 structurePhysical Review B, 1989
- Synthesis of bulk superconducting YBa2Cu4O8 at one atmosphere oxygen pressureNature, 1989
- Bulk synthesis of the 81-K superconductor YBa2Cu4O8 at high oxygen pressureNature, 1988
- Properties of Y-Ba-Cu-O thin films with ordered defect structure:Physical Review B, 1988
- Ordered-defect structure in epitaxialthin filmsPhysical Review B, 1988