Shin Hyung-Seop, Dedicatoria Marlon J, Gorospe Alking, Lee Sang-Heon
Department of Mechanical Design Engineering, Andong National University, Andong, Kyungbuk 760-749, South Korea.
Rev Sci Instrum. 2015 Mar;86(3):033907. doi: 10.1063/1.4915320.
The continued development in the design technology of practical superconducting devices adopting high temperature superconductors tapes has led to a deeper understanding of their electromechanical behaviors. Rare-earth-barium-copper-oxide coated conductor (CC) tapes exhibit anisotropy of transport property (Ic) under magnetic field and its intrinsic strain effect is much significant depending on the orientation to the tape surface and the magnetic field intensity applied. Different experimental systems have already been developed to measure the relation of Ic with mechanical strain ε, magnetic field intensity B, and its angle of orientation, θ. However, few systems and instruments can measure these relationships simultaneously; either Ic-B-θ or Ic-ε-B is usually measured. In this study, a device which can measure these influences simultaneously based on a pair of permanent magnet systems was constructed and the characteristic responses of critical current Ic with strain, magnetic field, and its orientation with respect to the CC tape surface were investigated. The angular dependence of Ic with strain at 77 K in reactive co-evaporation by deposition and reaction GdBCO CC tapes has been measured using the permanent magnet system. The orientation angle of magnetic field with respect to the tape's surface was varied by rotating the rig fixture that holds a pair of permanent magnets. The strain sensitivity of Ic at different angles under low magnetic field was evaluated. As a result, a characteristic surface Ic (ε, θ, B) has been constructed as the characteristic response of Ic with strain and varying orientation under magnetic field.
采用高温超导带材的实用超导装置设计技术的不断发展，使人们对其机电行为有了更深入的理解。稀土钡铜氧化物涂层导体（CC）带材在磁场下表现出输运特性（Ic）的各向异性，其固有应变效应根据与带材表面的取向以及所施加的磁场强度而有很大差异。已经开发出不同的实验系统来测量Ic与机械应变ε、磁场强度B及其取向角θ之间的关系。然而，很少有系统和仪器能够同时测量这些关系；通常只测量Ic - B - θ或Ic - ε - B。在本研究中，构建了一种基于一对永磁体系统能够同时测量这些影响的装置，并研究了临界电流Ic随应变、磁场及其相对于CC带材表面取向的特征响应。利用永磁体系统测量了在77 K下通过沉积和反应制备的GdBCO CC带材在反应共蒸发过程中Ic随应变的角度依赖性。通过旋转固定一对永磁体的装置夹具来改变磁场相对于带材表面的取向角。评估了低磁场下不同角度时Ic的应变灵敏度。结果，构建了一个特征表面Ic(ε, θ, B)，作为Ic在磁场下随应变和变化取向的特征响应。
