【摘要】 本文采用在液氮温度下的低温变形和室温下传统变形进行比较 ,系统研究了银包套单芯 ,银包套多芯 ,合金外包套银内包套多芯带材经过低温变形和室温变形后的组织结构 ,以及最终热处理后的电流传输性能和抗拉伸性能 .结果表明 ,低温变形过程中 ,由于外包套材料硬化 ,改善了外包套材料和超导芯之间的变形差异性 ,使得变形更有效地传递到陶瓷超导芯上 ,超导芯密度明显大于室温变形 ,银超界面相对平整 ,超导晶粒取向相对一致 .此外 ,低温变形后 ,Bi2 2 2 3带材的抗拉伸性能明显增加 .低温变形的这种作用对于银包套单芯和多芯带材试样十分明显 ,而对于合金外包套带材试样相对较小 .更多还原

【Abstract】 The effect of the cryogenic deformation on the Bi2223 superconducting tapes has been investigated in this paper. Mechanical deformation was carried out on the Ag-sheathed mono- and multi- filamentary Bi2223 and silver alloy-sheathed multi-filamentary Bi223 tapes at liquid nitrogen temperature (77K) and room temperature separately. Result shows that the critical current of the Bi2223 tapes is significantly enhanced by cryogenic deformation. The SEM microstructure observation shows that the cryogenic-tapes have higher core density, smoother silver/superconductor interface and better grain alignment. The tensile test shows that the tapes pressed at liquid nitrogen temperature have better tensile behavior than tapes pressed at room temperature.更多还原