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Microstructure of textured YBa2Cu3O7-δ prepared by the melted zone in magnetic field: texturation mechanism

1994; Elsevier BV; Volume: 235-240; Linguagem: Inglês

10.1016/0921-4534(94)91507-5

1873-2143

D. Bourgault, Jérôme Barbut, Jeanne Ayache, Daniel Chateigner, R. Tournier, F.J. Gotor, C. Bahezre, P. Germi, M. Pernet,

Magnetic and transport properties of perovskites and related materials

A zone melting set-up with a magnetic field perpendicular to the temperature gradient is used in order to optimize (a, b) plane alignment and thus critical current densities. Large samples with high Jc values in magnetic fields at 77K are obtained. These studies are carried out by optical microscopy, analytical transmission electron microscopy and X ray diffraction pole figures. Our results indicate that crystallite misorientation within a single domain does not exceed 10°. The application of a magnetic field of 5 T imposes the c-axis orientation during grain growth. Indeed, we observe an intergrain dispersion much smaller than 40° with respect to the magnetic field direction. The 123 matrix contains large amounts of unoriented 211 inclusions which are of different size.