REACTIVE SINTERING OF BI2SR2CACU2OX SUPERCONDUCTORS

Three phase assemblages were used to produce Bi2Sr2CaCu2Ox (2212) duri ng sintering: a mixture of 20% Ca-rich 2212 + 80% 2212, partially synt hesized 2212, and Bi2Sr2CuOx (2201) + (1/2 Ca2CuO3 + 1/2 CuO) (denoted 0011). The mixture of 2201 + 0011 produced highly pure 2212 within 50 h of heating in air at approximate to 850 degrees C. Ag tubes were fi lled with a mixture of 2201 + 0011 and worked into tapes by a powder-i n-tube process. Heat treatments produced microstructures consisting of small, highly textured 2212 grains. T-c values were approximate to 70 K. Transport Je values at 4.2K were approximate to 10(4) A/cm(2).