NB3AL SUPERCONDUCTING WIRE USING AN AL-ALLOY/NB JELLY-ROLL PROCESSING TECHNIQUE

NB3AL IS AN A-15 TYPE SUPERCONDDUCTOR WITH HIGHER TC, BC2 AND BETTER STRAIN TOLERANCE THAN NB3SN. IT IS AN ATTRACTIVE CANDIDATE MATERIAL FOR BUILDING HIGH-FIELD SUPERCONDUCTING MAGNETS IN THE FUSION AND HIGH ENERGY PHYSICS APPLICATIONS. BECAUSE THE STOICHIOMETRIC NB3AL NEEDS TO BE FORMED AT THE ELEVATED TEMPERATURES CLOSE TO ITS MELTING POINT, THE BRONZE TECHNIQUE IS NOT APPLICABLE IN THIS CASE AND THE MECHANICAL PROPERTY OF ALUMINUM DIFFERS FROM THAT OF NIOBIUM. IT IS NOT YET A PRACTICAL SUPERCONDUCTOR WHICH CAN BE FABRICATED IN AN INDUSTRIAL ENVIRONMENT. THE FEASIBILITY OF FABRICATING THE PRACTICAL NB3AL MULTIFILAMENTARY SUPERCONDUCTING WIRES THROUGH A JELLY-ROLL TECHNIQUE USING COMMERCIALLY AVAILABLE ALUMINUM ALLOY SHEETS, WHICH CONTAIN MG AND/OR SI, IS BEING INVESTIGATED. OFHC CU IS CONVENTIONAL WIRE FABRICATING PROCESSES WITH LOW TEMPERATURE EXTRUSION IS TESTED. THE SUPERCONDUCTING PROPERTIES OF THE NEW MATERIALS SUCH AS TC AND JC ARE MEASURED AND THE MIROSTRUCTURES OF THE SUPERCONDUCTING COMPOSITE MATERIALS EXAMINED AND CHARACTERIZED.