ELECTROMIGRATION OF OXYGEN IN YBA2CU3O7-DELTA

Electromigration (EM) in metals is used to produce directed particle fluxes within the material and can be used to change the composition of a given material or to purify it. EM experiments were performed on sintered YBa2Cu3O7- delta (YBCO) rods at 200 degrees C and 350 degrees C and the results were subsequently analysed by magnetic susceptibility and X-ray diffraction. Explorative trials showed that oxygen does migrate under the influence of the field in this material and motion is directed towards the cathode. Another remarkable feature during electromigration was that towards the cathode. Another remarkable feature during electromigration was that a decomposition reaction occurred at the anode, resulting in the formation of YBCO (tetragonal), CuO, Y2O3 and BaCO3 phases. It appears that the effects of electromigration will have a bearing on the stability of this material during use. © 1990 IOP Publishing Ltd.