Title :
Sol-Gel Insulation Coatings on
Wires for Coil Development
Author :
Arda, L. ; Boyraz, C. ; Sacli, O.A. ; Tomsic, M. ; Hascicek, Y.S.
Author_Institution :
Fac. of Arts & Sci., Bahcesehir Univ., Istanbul
fDate :
6/1/2008 12:00:00 AM
Abstract :
In this study, preparation, structure, morphology and thermal properties of ceramic insulation coating on Monel/Fe/MgB2 wires, which were fabricated by Hyper Tech Research Inc., using Continuous Tube Forming and Filling (CTFF) process were studied for coil development. Ceramic insulation coatings were prepared by reel-to-reel sol-gel method using solutions of Y and Zr based organometallic compounds. The coating thickness was controlled by number of coating, withdrawal speed and solution chemistry. 29 meter of Monel/Fe/MgB2 wire was insulated by Y2O3-ZrO2 using sol-gel method. Monel/Fe/MgB2 coil was layer wounded and impregnated with stycast. Sister samples of coil were tested between 4.2 K and 30 K with a Variable Temperature Insert (VTI) in a 20 T superconducting magnet using the analog DC pulse four-wire method with 1 (muV/cm) criterion. The sample had a Jc of 0.16 times 105 (A/cm2) at 4 T at 21 K. The surface morphologies and microstructure of sister samples of coil were characterized by ESEM, EDS, DTA, TGA and XRD. Resistance was measured by using HP 4339A High Resistance Meter.
Keywords :
X-ray chemical analysis; X-ray diffraction; ceramics; copper alloys; critical currents; differential thermal analysis; forming processes; insulating coatings; iron; magnesium compounds; nickel alloys; scanning electron microscopy; sol-gel processing; superconducting coils; surface morphology; type II superconductors; yttrium compounds; zirconium compounds; CuNi-Fe-MgB2-Y2O3-ZrO2; DTA; EDS; ESEM; Monel/Fe/MgB2 wires; TGA; XRD; ceramic insulation coating; coating thickness; coil; continuous tube forming-filling process; critical current; magnetic flux density 20 T; microstructure; resistance; sol-gel method; surface morphology; temperature 4.2 K to 30 K; thermal properties; ${rm MgB}_{2}$ coil; ${rm Y}_{2}{rm O}_{3}{hbox{-}}{rm ZrO}_{2}$; Insulation; sol-gel;
Journal_Title :
Applied Superconductivity, IEEE Transactions on
DOI :
10.1109/TASC.2008.920819