PROCESSING OF THE Tl-Ca-Ba-Cu-O HIGH Tc PHASE VIA THE SOL-GEL ROUTE

Tl2CaBa2Cu2O8+x and Tl2Ca2Ba2Cu3O10+x superconductors were produced by a sol-gel route using alkoxide precursors. The superconductors were characterised by XRD, magnetic susceptibility, four-point probe resistivity, chemical analysis and SEM. The 2122 and 2223 superconducting phases were produced using 3:2:2:3 and 1:3:1:3 starting ratios, respectively. Tc(zero) values were 105 (2122) and 115 (2223) K with increases in these transitions occurring with firing times. Microstructural analysis revealed that a large degree of directional plate-like crystal growth occurred on the surface of the pellets. 11 refs.