Refinement of Nb3Sn grain size by the generation of ZrO2 precipitates in Nb3Sn wires

X. Xu; M. Sumption; X. Peng; E. W. Collings

doi:10.1063/1.4866865

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arXiv · 1402.3001

Refinement of Nb3Sn grain size by the generation of ZrO2 precipitates in Nb3Sn wires

X. Xu·M. Sumption·X. Peng·E. W. Collings

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Abstract

In this letter we demonstrate that if oxygen can be properly supplied to (Nb-Zr)-Sn wires, ZrO2 precipitates will form during the heat treatment, refining the Nb3Sn grain size markedly. Here, a Nb3Sn subelement was fabricated in which Nb-1Zr alloy was used, and oxygen was supplied via SnO2 powder. The results showed that such a design could supply sufficient oxygen to internally oxidize the Zr in the Nb-1Zr alloy, and that the sample reacted at 650 {\deg}C had grain sizes of ~45 nm, less than half the size of the grains in present Nb3Sn conductors. Magnetic measurements showed that the peak of the pinning force vs. field (Fp-B) curve was shifted to ~0.3Birr (the irreversibility field).

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X. Xu, M. Sumption, X. Peng, E. W. Collings. 2014-02-12. Refinement of Nb3Sn grain size by the generation of ZrO2 precipitates in Nb3Sn wires. https://doi.org/10.1063/1.4866865

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