Fully dense MgB2 superconductor textured by hot deformation

Bulk textured MgB2 material of nearly full density showing a weak c-axis al ignment of the hexagonal MgB2 grains parallel to the pressure direction was obtained by hot deformation of a stoichiometric MgB2 pellet prepared by a gas-solid reaction. The texture of the material was verified by comparing t he X-ray diffraction patterns of the hot deformed material with isotropic M gB2 powder. A small, but distinct anisotropy of the upper critical field up to H-c2(a,b)/H-c2(c) similar to 1.2 depending on degree of texture was fou nd by resistance and susceptibility measurements. No anisotropy of the crit ical current density determined from magnetization measurements was found f or the textured material. (C) 2001 Elsevier Science B.V. All rights reserve d.