Compound-superconducting coil

摘要

A compound-superconducting coil of the type including a plurality of superconducting wires in a tube and forcing a coolant through the tube. The subject compound-superconducting coil comprises a plurality of compound-superconducting wires and a tube for receiving the plural wires. Void spaces are provided in the interior of the tube to allow for the passage of a coolant. The void fraction is 45% to 70% of the tube interior. The subject compound-superconducting coil, when brought to a superconducting condition, allows for the passage of a current whose magnitude accounts for at least 80% of a critical current observed when the wire is strain-free state.