In:
Journal of Materials Research, Springer Science and Business Media LLC, Vol. 7, No. 12 ( 1992-12), p. 3194-3201
Kurzfassung:
Grain growth in the GdBa 2 Cu 3 O 7−δ high T c superconductor was investigated. The composition Gd 1.09 Ba 1.91 Cu 3 O 7−δ , within the solid solubility region, was selected for the present grain growth study. Differential thermal analysis did not reveal any thermal event except the incongruent melting point, which is indicative of the absence of a liquid second phase during grain growth. The final densities of isothermally annealed samples ranged from 91.3% to 93.7% of theoretical density. The microstructure observation showed a greater grain aspect ratio in this material than in YBa 2 Cu 3 O 7−δ . The average grain aspect ratio was about 4.7. A very low grain growth exponent of 0.07 was found in the isothermal annealing temperature range from 965 °C to 1020 °C. By comparison with the results on the YBa 2 Cu 3 O 7−δ system previously reported, it was concluded that the grain growth kinetics in these materials are strongly controlled by the anisotropy of the grain boundary energy. The activation energy of grain growth was calculated to be about 77 kJ/mole.
Materialart:
Online-Ressource
ISSN:
0884-2914
,
2044-5326
DOI:
10.1557/JMR.1992.3194
Sprache:
Englisch
Verlag:
Springer Science and Business Media LLC
Publikationsdatum:
1992
ZDB Id:
54876-5
ZDB Id:
2015297-8
