EFFECT OF SINTERING TIME ON Tc OF Bi-Pb-Sr-Ca-Cu-Hf-O

The effects of hafnium addition on heat treatment time to achieve 100 K of T c are investigated for the Bi oxide. The high T c is found of the Bi 1.6 Pb 0.4 Sr 2 Ca 2 Cu 2.4 Hf 0.6 O x sample annealed for the short period of the heat treatment. Based on the diffraction discussion, the Tc change can be explained.