Radial stress influence on high current density superconducting magnet performance with large and small bore

Dry-wound superconducting solenoid offers a good manufacturability of high current density magnet but occasionally suffers from premature quenches triggered by small heat generated within the magnet. Principal source of heat is thought to be conductor motion induced frictional heating and/or filler material fracture released energy in windings. This paper describes stress analysis, training performance and their relation for both the large bore and the small bore magnets constructed and tested to establish stability of the dry-wound superconducting solenoid. The results suggested that conductor motion took place even though radial stress in the magnet was still compressive and a conductor was expected in its original position. They also suggested that same stress condition in both large and small bore magnets triggered premature quenches even though they have difference in major specification.