Comparative measurements of ITER Nb3Sn strands between two laboratories

J. Lu; S. Hill; D. McGuire; K. Dellinger; A. Nijhuis; W. A. J. Wessel; H. J. G. Krooshoop; K. Chan; N. N. Martovestky

doi:10.1109/tasc.2017.2685502

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arXiv · 1701.00446

Comparative measurements of ITER Nb3Sn strands between two laboratories

J. Lu·S. Hill·D. McGuire·K. Dellinger·A. Nijhuis·W. A. J. Wessel·H. J. G. Krooshoop·K. Chan·N. N. Martovestky

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Abstract

ITER Nb3Sn strand quality verification tests require large quantities of precise measurements. Therefore regular cross-checking between testing laboratories is critically important. In this paper, we present results from a cross-checking test of 140 samples between the National High Magnetic Field Laboratory, USA and the University of Twente, the Netherlands. The tests comprise measurements at 4.2 K on critical current, RRR and hysteresis loss, while at room temperature the chromium layer thickness, Cu/nonCu ratio, filament twist pitch, and diameter were determined. Our results show very good agreement between the two labs. The reasons for small random discrepancies are discussed.

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J. Lu, S. Hill, D. McGuire, K. Dellinger, A. Nijhuis, W. A. J. Wessel, H. J. G. Krooshoop, K. Chan, N. N. Martovestky. 2016-12-17. Comparative measurements of ITER Nb3Sn strands between two laboratories. https://doi.org/10.1109/tasc.2017.2685502

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