Patent ID: 6894006
Filing Date: 2005-05-17
Classification: C04B,H01L

Abstract:
1. In a method for producing a Pb doped Bi-2223 superconductor including multiple heating steps, the improvement comprising reducing the concentration of non-superconducting phases during the initial heat treatment of Pb doped Ag/Bi-2223 composites having Bi-2223 and Bi-2212 superconducting phases by, providing a Pb doped Ag/Bi-2223 composite having Bi-2223 and Bi-2212 superconducting phases, heating the composite in an atmosphere having an oxygen partial pressure not less than about 0.04 atmospheres, maintaining the temperature at the lower of a non-superconducting phase take-off temperature and the Bi-2223 superconducting phase grain growth take-off temperature, varying the oxygen partial pressure and/or the temperature between about 815° C. and about 835° C. to produce not less than about 80 percent conversion to Pb doped Bi-2223 superconducting phase and not greater than about 20 volume percent non-superconducting phases, and thereafter continuing treatment of the superconducting material to produce a final product.