27 August 2017 to 1 September 2017
RAI Congress Center, Amsterdam, The Netherlands
Europe/Amsterdam timezone

Irreversible strain characteristics of technical RHQT Nb3Al superconductors

28 Aug 2017, 13:15
1h 45m
Posters Area

Posters Area

Poster Presentation of 1h45m F1 - Low-Tc Wires and Cables Mon-Af-Po1.08

Speaker

Nobuya Banno (National Institute for Materials Science)

Description

In the ITER magnets consisting of Nb3Sn conductors, the magnets are fabricated through the so-called wind & react (W & R) technique. In the W & R process, the conductors are wound prior to the heat treatment to form the Nb3Sn superconducting strands from the non-superconducting ductile precursor ones. Then the heat-treated windings are encased into the radial plate keeping their winding shape as it is. The Nb3Sn strands have lower strain sensitivity, so that the applied bending strain to the Nb3Sn strands should be suppressed as small as possible. However in DEMO reactor magnets whose size becomes much larger than the ITER ones, the problems concerning dimension accuracy and fabrication cost should become much bigger. In this context, the react & wind (R & W) process would have to be considered as a solution to construct the magnets. The Nb3Al strands have small strain sensitivity for Jc characteristics. Hence, they could be one of the alternative conductors for realizing the R & W coil. In the R & W application, the irreversible strain characteristics of the strand should be also an important factor as well as the strain sensitivity. The irreversible strain limit should be an index indicating how much the strand is bendable. Hence in this study, we compared the irreversible strain characteristics of various technical rapid-heating, quenching and transformation-processed (RHQT) Nb3Al strands with a different matrix material and filament diameter.

Submitters Country Japan

Primary authors

Nobuya Banno (National Institute for Materials Science) Gen Nishijima (National Institute for Materials Science) Dr Hitoshi Kitaguchi (National Institute for Materials Science) Katsumi Miyashita (SH Copper Producrs co., Ltd) Dr Yoshihiko Ninoya (National Institute for Quantum and Radiological Science and Technology) Mr Tomone Suwa (National Institutes for Quantum and Radiological Science and Technology) Hidemasa Ozeki (National Institutes for Quantum and Radiological Science and Te) Dr Yoshikazu Takahashi (National Institutes for Quantum and Radiological Science and Technology)

Presentation Materials