Longitudinal uniformity of MgB2 wires made by an internal magnesium diffusion process. (20th August 2021)

• Record Type: Journal Article
• Authors: Kováč, P; Hušek, I; Hain, M; Kopera, L; Melišek, T; Berek, D
• Is Part Of: Superconductor science & technology. Volume 34:Number 9(2021)
• Publication Date: 2021-08-20
• Subjects: uniformity -- internal Mg diffusion (IMD) -- long MgB2 wire -- critical currents; Superconductivity -- Periodicals; Superconductors -- Periodicals; 537.623
• DOI: 10.1088/1361-6668/ac191b
• Languages: English
• ISSNs: 0953-2048

Abstract

Abstract: Single- and multi-core MgB2 wires have been fabricated by an internal Mg diffusion (IMD) process. Wires uniformity after drawing and/or rolling deformation has been studied by optical microscopy and x-ray micro-tomography. Several short samples taken lengthwise between both ends of the wire were annealed and their critical current measured. It was found that I c of the single-core barrier-free MgB2 /Fe wire with high fill factor (32.5% of MgB2 ) vary by 100% towards the averaged I c . Multi-core wire having ∼15.0% of MgB2 and Cu outer sheath shows better uniformity with 25% deviation of I c over the 10 m length, which is still quite low and needs some improvements. It is expected, that improved in-length uniformity can be reached only for filamentary IMD wires with optimized deforming process and mechanically stronger outer sheath.