TEXTURED JOINTS FOR CONDUCTORS AND COMPLEX-SHAPED COMPONENTS USING THE COMPOSITE REACTION TEXTURING METHOD

A new technique for forming textured high critical current joints betw een superconducting ceramic artefacts is presented. The method uses co mposite reaction texturing (CRT). For the Bi2Sr2Ca1Cu2OX (Bi-2212) sys tem, Bi-2212 performed is seeded with specifically aligned MgO whisker s which determine the texture in the joint region during a subsequent reaction treatment that involves partial melting. The technique can be used to loin green or previously reacted components and if binders ar e used polymer joining techniques can be exploited. Samples retain the ir shape for repeated partial melting. Although it is also possible to Join previously reacted components by use of a lower melting point Bi -2212 compound (e.g. Li doped). The quality of joints was assessed by transport measurements on joined bars and magnetisation measurements o n Cylinders formed from polymer processed sheet. It was found that the joint region carried as large a critical current as non-joint section s, For the rare earth system, RBa(2)Cu(3)O(X) (R-123), a variation of the above technique can be used to form joints.