Wind and React and React and Wind ${\rm MgB}_{2}$ Solenoid, Racetrack and Pancake Coils

Abstract

Multifllamentary MgB <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> wire was used to construct three coils that were tested for transport J <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</sub> and magnetic field in the bore between 4.2 K and 30 K. The solenoid coil achieved 85 A at 4.2 K with 3.9 T in a 3.8 cm bore. A racetrack coil was also fabricated with an attached compression plate to test the effects of compressive stress on an MgB <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> racetrack coil. At compressive stresses up to 52 MPa, no degradation was observed in transport J <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</sub> at 20 K. A react and wind coil with a 56 cm bore and 828 m of MgB <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sub> wire was also tested for transport J <sub xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">c</sub> and magnetic field in the bore to demonstrate the feasibility of the react and wind process. At 5 K, the react and wind coil achieved 168 A and 0.17 T.