多芯Bi-2212线材加工均匀性的对比  

The Comparison for Process Uniform of Multi-core Bi-2212 Wire

作　　者：李高山[1] 郝清滨[1] 张胜楠[1] 李成山[1] 

机构地区：[1]西北有色金属研究院超导材料研究所,西安710016

出　　处：《材料导报（纳米与新材料专辑）》2014年第1期107-109,115,共4页

基　　金：国家自然科学基金(51102198);ITER计划专项(2013GB110001)

摘　　要：Bi-2212超导体是唯一可制备成各向同性圆线且具有高载流性能的高温超导材料,但要实现真正的应用,必须进一步提高线材的载流性能。对比了传统结构线材和芯部增强结构线材的加工特性,研究了传统结构线材的断芯机制。研究结果表明:拉拔过程中线材中心的拉伸应力大于边缘区域的拉应力,再加上Bi-2212陶瓷粉末的塑度较差,导致脆弱的Bi-2212线材在中心首先出现断芯,随着加工的继续,这种断芯现象向周围扩展,甚至最终中心芯丝完全断裂;而中心增强的Bi-2212线材则可以有效避免中心芯丝的断裂,提高了线材的加工的均匀性,大大降低了线材的断芯率,芯丝的断芯率由以前的15%减低到5%以下,同时也大大提高了线材的载流性能。通过控制线材热处理过程中的晶须可进一步提高线材的载流性能。As the high temperature superconducting material Bi-2212 wires could be made to produce the isotro-py wire which had high carrying current performance. In order to put the material into application, its carrying currentperformance must be improved. The paper included the comparison with traditional structure wire and the processingcharacters with the core strengthen structure wire, it also researches the breaking core character in the traditionalstructure wire. The result showed the tensile stress was bigger on the center than the edge of Bi-2212 wire during thedrawing＇ the Bi-2212 could have the breaking core for the Bi-2212 ceram powder had the poor plasticity. During theprocess, the breaking core spreaded on every side even the core filaments were broken. The center strenghted Bi-2212wire could avoid the core filaments breaking; it could improve the processing uniform for the wires and also reduce thebreaking coil ratio. The breaking coil ration was reduced from the 15＇ to 5＇, it also improved the carrying currentperformance. The carrying current performance could he improved by controlling the whisker during the heat treat-ment for the wires.

关 键 词：Bi-2212线 晶须 均匀性 

分 类 号：TG148[一般工业技术—材料科学与工程]