A NOVEL APPROACH TO FABRICATION OF NIOBIUM-TIN CONDUCTOR WITH ARTIFICIAL PINNING CENTERS

THE SIGNIFICANCE OF ENGINEERED ARTIFICIAL PINNING CENTERS (APC) IN NIOBIUM-TITANIUM (NBTI) SUPERCONDUCTORS HAS BEEN RECOGNIZED WORLD WIDE AND TODAY IS ONE THE MOST IMPORTANT AREAS OF MATERIALS RESEARCH IN APPLIED SUPERCONDUCTIVITY. SO FAR THIS APPROACH HAS YIELDED RECORD HIGH CRITICAL CURRENTS (JC) BELOW 4 TESLA (T) FIELD RANGE AND AT SOME SELECT FIELDS ALMOST A FACTOR OF TWO BETTER, SURPASSING THAT OF THE CONVENTIONALLY OPTIMIZED NBTI WIRES. THE IMPORTANCE OF THE EXISTENCE OF A HIGH PERFORMANCE AND ECONOMICAL NIOBIUM-TITIANIUM (NB3SN) CONDUCTOR IN THE UNITED STATES IS THE MAIN JUSTIFICATION FOR THIS PHASE I EFFORT. THE PHASE I WORK WILL DETERMINE WHETHER THE ENGINEERING OF ARTIFICIAL PINNING CENTERS INTO NB3SN WIRE WILL HAVE SIGNIFICANT IMPACT ON THE CRITICAL CURRENT DENSITY. IN ADDITION TO POSSIBLE COST REDUCTION THROUGH INCREASED CONDUCTOR PERFORMANCE, THIS PHASE I PROJECT WILL INTRODUCE A NOVEL DESIGN APPROACH WHICH WILL HAVE FURTHER IMPACT ON COST REDUCTION BY ELIMINATING THE NEED FOR A DIFFUSION BARRIER AND THEREFORE ELIMINATING A SEPARATE STABILIZER BILLET TYPICAL OF TODAY'S INTERNAL TIN PROCESS.