THE EFFECT OF THE CONFIGURATION OF THE SILVER LAYER ON TEXTURE GROWTHAND MICROSTRUCTURE IN SILVER-SHEATHED (BI,PB)(2)SR2CA2CU3OX SUPERCONDUCTING TAPE

Silver-sheathed (Bi, Pb)(2)Sr2Ca2Cu3Ox(2223) tapes with different conf igurations of silver layer have been prepared to investigate the effec t of the silver layer on texture growth and microstructure of the 2223 phase by x-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive x-ray analysis (EDAX). It has been shown that th e whole silver layers, both lateral and broad layers, significantly en hance texture growth of the 2223 phase. The new understanding of the m echanistic role of the silver layer in texture growth has been present ed, based on the high solubility of oxygen in silver and the greater a bility of silver with respect to adsorption of oxygen. The silver laye r is thought to supply both a fast out-diffusion path for oxygen forme d during the transition from the 2212 phase to the textured 2223 phase and a favourable configuration for texture growth of the 2223 phase.