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Fully dense MgB_2 superconductor textured by hot deformation

A. Handstein·D. Hinz·G. Fuchs·K. -H. Müller·K. Nenkov·O. Gutfleisch·V. N. Narozhnyi·L. Schultz
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Abstract

Bulk textured MgB_2 material of nearly full density showing a weak c-axis alignment of the hexagonal MgB_2 grains parallel to the pressure direction was obtained by hot deformation of a stoichiometric MgB_2 pellet prepared by a gas-solid reaction. The texture of the material was verified by comparing the x-ray diffraction patterns of the hot deformed material with isotropic MgB_2 powder. A small, but distinct anisotropy of the upper critical field up to Hc2^{a,b}/Hc2^{c}~1.2 depending on degree of texture was found by resistance and susceptibility measurements. No anisotropy of the critical current density determined from magnetization measurements was found for the textured material.

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A. Handstein, D. Hinz, G. Fuchs, K. -H. Müller, K. Nenkov, O. Gutfleisch, V. N. Narozhnyi, L. Schultz. 2001-06-05. Fully dense MgB_2 superconductor textured by hot deformation. https://arxiv.org/abs/cond-mat/0103408

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