Title :
Magnetic properties and microstructure of V/sub 3/Si multifilamentary superconductors
Author :
Takeuchi, T. ; Kim, Y.B. ; Itoh, K. ; Nemoto, Y. ; Iijima, Y. ; Kosuge, M. ; Inoue, K. ; Maeda, H.
Author_Institution :
Tsukuba Magnet. Labs., Nat. Res. Inst. for Metals, Ibaraki, Japan
fDate :
6/1/1995 12:00:00 AM
Abstract :
Magnetic properties, in correlation with cross-sectional microstructures, were studied in order to check the potentiality of V/sub 3/Si multifilamentary superconductors for AC use. Irregularity of V filaments brings about the bridging between filaments during heat treatments. The effective filament diameter D/sub eff/ of 2.3 /spl mu/m is, however, comparable to that of bronze processed Nb/sub 3/Sn conductors. At long heat treatments, the V/sub 5/Si/sub 3/ layer initially forming around V/sub 3/Si filaments disappears, and then proximity coupling occurs additionally to the bridging. The proximity coupling causes the two peaks to appear in the magnetization curves and D/sub eff/ to increase at low fields. The existence of V/sub 5/Si/sub 3/ is quite effective in reducing D/sub eff/ and hence hysteresis loss.<>
Keywords :
crystal microstructure; heat treatment; magnetic hysteresis; multifilamentary superconductors; proximity effect (superconductivity); silicon alloys; superconducting materials; vanadium alloys; 2.3 mum; AC use; V/sub 3/Si; cross-sectional microstructures; filament bridging; filament diameter; heat treatment; hysteresis loss; magnetization curves; multifilamentary superconductors; proximity coupling; Conductors; Couplings; Heat treatment; Magnetic hysteresis; Magnetic properties; Magnetization; Microstructure; Multifilamentary superconductors; Niobium; Tin;
Journal_Title :
Applied Superconductivity, IEEE Transactions on