Enthalpy stabilized superconducting magnets

An essential requirement for complete stabilization of a superconducting magnet is adequate circulation of liquid helium in the winding, resulting in a low average current density, in partially stabilized magnets, the size of the cooling channels is reduced, but access for liquid helium is still considered necessary. With enthalpy stabilization, however, the need for helium penetration into the winding is eliminated, resulting in better packing of the conductors and a higher average current density. A small enthalpy stabilized magnet has been tested that was fully impregnated with epoxy resin and operated at a current density above 10⁴A/cm². The basis of the design of such magnets is discussed, with particular reference to the choice of conductor size and its effect on average current density in the magnet. Possible applications of this technique are also discussed.