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采用粉末装管法制备了Ｍ２７ （２７ 芯）， Ｍ１９ （１９ 芯） 六种铋系银包套高温超导多芯带材， 利用标准四引线法测量其电学性能临界温度（Ｔｃ） 和临界电流密度（Ｊｃ）， 利用高分辨电子显微镜， 配有能谱仪的透射电子显微镜和扫描电子显微镜研究其显微组织结构。超导多芯带材的相组成以２２２３ 相为主， 可以观察到少量的２２１２ 相， 且与２２２３ 相共生。在超导相晶粒之间和三叉晶界存在非晶层。超导相界面、超导相和银包套界面较为平直， 超导相和银包套界面夹角为５°。超导相的晶粒具有一定的织构， 晶粒的ａｂ 面大致平行于带材的带长方向，ｃ 轴大致垂直于轧面。扫描电子显微镜观察表明国外超导带材的晶粒较国内大而明显。在样品中存在ＣｕＯ、ＳｒＯ和ＣａＯ杂相。一些杂相在超导相的周围沿晶界分布， 一些杂相独立存在。
Six kinds of bismuth-silver-coated high-temperature superconducting multi-core tapes with M27 (27 cores) and M19 (19 cores) were prepared by powder tube method. The critical temperature (Tc) and critical current Density (Jc), and the microstructure was studied by high resolution electron microscope, transmission electron microscope with a spectrometer and scanning electron microscope. The phase composition of the superconducting multi-core tape is mainly composed of 2223 phase, a small amount of 2212 phase can be observed and it is symbiotic with 2223 phase. An amorphous layer exists between the superconducting-phase grains and the triple-crystal grain boundary. Superconducting phase interface, superconducting phase and silver envelope interface is relatively straight, superconducting phase and silver envelope interface angle of 5 °. The grains of the superconducting phase have a certain texture. The ab plane of the grains is substantially parallel to the strip length direction, and the c-axis is approximately perpendicular to the rolling surface. Scanning electron microscopy showed that foreign superconducting tape grain larger than the domestic obvious. CuO, SrO and CaO hetero phases are present in the sample. Some heterophases are distributed along the grain boundaries around the superconducting phase, and some heterogeneous phases exist independently.