Suppression of the critical current degradation under the compressive stress on the internal reinforcement bronze processed Nb3Sn wire using Cu-Sn-In ternary bronze alloy matrix
Suppression of the critical current degradation under the compressive stress on the internal reinforcement bronze processed Nb3Sn wire using Cu-Sn-In ternary bronze alloy matrix
复制标题
使用 Cu-Sn-In 三元青铜合金基体的内强化青铜加工 Nb3Sn 线在压应力下抑制临界电流退化
DOI：
10.1016/j.fusengdes.2021.112365
复制
发表时间：
2021
影响因子：
1.7
通讯作者：
S. Awaji and A. Kikuchi
中科院分区：
文献类型：
--
作者：
Y. Hishinuma;H. Oguro;H. Taniguchi;S. Awaji and A. Kikuchi
典型的大电流聚变磁体导线通常采用管道中电缆(CIC)方法制造。CIC导体是由多股Nb3Sn线和纯铜线绞合而成的，具有巨大的局部应力/应变集中。在基于电磁力的横向压缩载荷下，每股绞合的Nb3Sn线都观察到点接触。这些浓度导致了Nb3Sn丝的断裂，也是CIC导体均流温度(TCS)和临界电流密度(JC)下降的主要因素。为了在未来的演示中实现更高电磁力下的超导磁体，需要提高Nb3Sn线的机械强度。最近，我们成功地用含铟(In)元素的铜-锡系三元合金基材制备了内增强青铜Nb3Sn多芯线材，并用原位压应力评价了该线材的临界电流特性。内衬增强Nb3Sn线在150 Mpa时的压应力为5%，是未增强Nb3Sn线的3倍。我们发现，内部基质增强是抑制压应力降解的一种很有优势的方法。
Typical large current capacity conductors for fusion magnet are often manufactured by the Cable-In-Conduit (CIC) method. The CIC conductor is fabricated by twisting multiple Nb3Sn strands and pure Cu wires, and huge local stress/strain concentration alike the point contact was observed in each twisted Nb3Sn strand applied to transverse compressive load based on the electromagnetic force. These concentrations caused to the Nb3Sn filament breakage and it was also a major factor of the current sharing temperature (Tcs) and critical current density (Jc) degradation on CIC conductor. Mechanical strength improvement of the Nb3Sn strand is required to realize superconducting magnet under higher electromagnetic force for a future DEMO. Recently, we succeeded to fabricate the internal matrix reinforcement bronze processed Nb3Sn multifilamentary wire using a Cu-Sn system ternary alloy matrix containing Indium (In) element.In this study, critical current (Ic) property with the in-situ compressive stress on the internal matrix reinforcement Nb3Sn wire was evaluated. The compressive stress obtained to theIcdeterioration of 5% on the internal matrix reinforcement Nb3Sn wire was confirmed at 150 MPa, and this stress was 3 times higher than Nb3Sn wire without reinforcement. We found that the internal matrix reinforcement was one of the great advantage methods to suppress theIcdegradation by the compressive stress.