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The closed electric circuit concept is used for critical current and stability measurements of [Nb.sub.3]Sn multi-strand superconducting cables. Significant degradation is observed in the critical current of the cable when the average compressive stress is about 20 MPa, which is found to be irreversible after unloading.

The article examines the degradation due to transverse loading under high magnetic field. Findings reveal an irreversible degradation due to compressive stress of around 30 MPa.

A cryogen-free 19 T superconducting magnet with a 52-mm room temperature bore is developed. The mechanical properties are investigated for oxide superconducting Bi-2223 tapes.

The deformation and fracture behavior is studied in Sm123 bulk superconductors by comprehensive loading at room temperature. The effects of specimen length on the compressive mechanical properties are discussed.

Melt-processed bulk superconductors are used to construct a superconducting permanent magnet system.

Vickers hardness characteristics of bulk superconductors are examined at cryogenic temperatures.

The influence of magnetic fields on the mechanical properties and strain/stress dependence of the critical current of Nb-matrix Nb3Sn multifilamentary wires is studied by means of an axial tensile testing apparatus. Results show that the strain sensitivity of the critical current is the same as the reversible strain limit. The data also suggest that the wires are highly tolerant to external stress/strain.

The effect of residual strain on the critical current flow in bronze processed multifilamentary Nb3Sn superconducting wires reinforced with CuNb is studied by means of an estimation technique based on the rule of mixtures. Results show that the effect of residual strain on the critical current denity of the wires is negligible and fundamentally similar to that of monolithic wires.

The development of a multifilamentary Nb3Sn wire containing a copper niobium (CuNb) stabilizer is reported. Fabricated via the bronze process, the Nb3Sn/CuNb wire's electrical characteristics at 23 T and 4.2 K include a residual resistance ratio of 20 and a 0.2-micro-ohm.cm magnetoresistance. Its mechanical strength and superconducting properties suggest that it is suitable for use in high-field superconducting magnets

It was reported that Lorentz force caused degradation of critical current in the ITER-TFMC conductor. We have used our novel experimental setup, which utilizes the closed electric circuit concept for critical current and stability measurements of multi-stand superconducting cables. The feature of this setup is mechanical loading applied to the multi-strand cable in the transverse direction. Significant degradation in the critical current of the cable was observed when the average compressive stress was about 20 MPa. This degradation was found irreversible after unloading. We tested the cable with epoxy or ice molds as well. No degradation was observed in the molded cables. We also tested the cable with smaller void fraction. In this case, significant degradation in critical current was observed. [ABSTRACT FROM AUTHOR]

We developed a novel critical current and stability experimental setup utilizing a closed electric circuit with a multi-stand superconducting cable. The feature of this setup is transverse mechanical loading implied to the multi-strand cable in the transverse direction. It was reported that Lorentz force caused degradation of critical current in the ITER-TFMC conductor. Furthermore, these phenomena were only observed in the ITER full size conductors with large Lorentz forces under high magnetic field. The advantage of our setup is a critical current measurement with comparable mechanical stress under high magnetic field. Employing an inductive critical current measurement technique, we conducted the experiment with transport current of around 10 kA without any power supply nor current lead. As experimental results, we observed significant degradation due to compressive stress of around 30 MPa. This degradation was found irreversible, when it was unloaded. [ABSTRACT FROM AUTHOR]