Presentation Information
[WB1-03-INV]Examination and improvement of strain tolerance of MgB2 wires
*Hideki Tanaka1, Motomune Kodama1, Takaaki Suzuki1, Hiroshi Kotaki1, Akiyoshi Matsumoto2, Gen Nishijima2 (1. Hitachi, Ltd. (Japan), 2. National Institute for Material Science (Japan))
Keywords:
MgB2 wire,Strain tolerance,React and wind
MgB2 wires can be used around 20 K and have the characteristic of being easy to use as multi-filament round wires. It is well known that the critical current (Ic) of heat-treated MgB2 wires degrades when subjected to strain exceeding the irreversible strain. The wind-and-react method is a way to create magnets without compromising the performance of the wire, and we have demonstrated MgB2 coil and applied device using this method.To improve the winding accuracy of MgB2 coils, reduce manufacturing costs, and expand applications, MgB2 coils should be manufactured using the react-and-wind method. We have investigated the mechanism of strain tolerance in MgB2 wires and improved their strain tolerance. Wire reinforced with SUS exhibits an irreversible strain of 0.6% at room temperature, and the coil made by react-and-wind using this wire showed no degradation in Ic performance. In this presentation, the mechanism of strain tolerance will be mainly reported. In addition, some of the Ic measurements were conducted using the NIMS Open Facility (NOF).