【摘要】 本文通过控制粉末的烧结温度 ,得到三种由不同相含量组成的前驱粉末 ,并采用这些前驱粉末制备出超导带材 .通过对带材的显微结构的观察和临界电流密度的测量表明 ,前驱粉末的相组成对 (Bi,Pb) 2 2 2 3/银超导带材的显微结构和临界电流密度有很大影响 .采用不同的前驱粉末所制备的带材具有不同的临界电流密度 ,带材的临界电流密度取决于所形成的微观组织 .通过SEM观察三种带材的微观组织发现 ,样品中的杂相 (第二相 )主要是残留的 2 2 1 2相 ,(Sr,Ca) 2 CuO3 相和CuO相 ,这些残留相的生成与前驱粉末中各相比例的失衡有关 .杂相的尺寸 ,含量及其形状是影响带材临界电流密度的主要因素 .因此 ,获得合理的前驱粉末相组成是改善带材超导性能的关键之一 .更多还原

【Abstract】 Three precursor powders were calcined at different temperature. Three (Bi,Pb)-2223 tapes were made from these precursor powders. Effects of precursor powder on microstructure and critical Current density of (Bi,Pb)-2223 tapes were studied in this paper. The result shows that the microstructure and the critical current density of tapes were strongly dependent on the phase composition in precursor powder. J-c was controlled by the microstructure of the tape. The microstructure was observed by SEM. SEM shows that there are more 2212, (Sr,Ca)-2CuO-3 and CuO in the tapes. Some secondary phases come from the precursor powder. Size, shape and content of the secondary phases influence the critical current density of tapes. In conclusion, we believed that a reasonable phase composition in the precursor powder would be important to obtain the good microstructure and high J-c in tape.更多还原