Effects of Ag addition on the diffusion reaction in high-T/sub c/ oxides

The effects of Ag addition on the diffusion reaction for synthesizing high critical temperature, T/sub c/, oxides are described. The Ag addition to the diffusion component enhances the diffusion, and decreases the optimum reaction temperature. In the Y-123 and Bi-2212 diffusion specimens, the Ag goes up to the surface of the specimen, improving the grain alignment of the diffusion layer. In the Tl-2223 diffusion specimen, an offset T/sub c/ of 116 K and a large critical current (77 K, 0 T) are obtained. The diffusion layer composed of Sr-Ca-Cu oxides formed in the (Bi/sub 0.8/Pb/sub 0.2/)/sub 2/CuO/sub y/+Ag/SrCaCuO/sub 3/ diffusion composite shows a sharp resistance drop around 150 K and an offset of T/sub c/ of 120 K.<>