DEVELOPMENT OF AN IMPROVED COMPOSITE SUPERCONDUCTOR WITH ELECTRICALLY UNCOUPLED FINE NBTI FILAMENTS AND A HIGH CURRENT DENSITY

IN RECENT MONTHS, BY THE USE OF DIFFUSION BARRIERS, HIGH HOMOGENEITY RAW MATERIAL AND IMPROVED HEAT TREATMENTS, HIGH JC FINE FILAMENT COMPOSITE SUPERCONDUCTORS HAVE BEEN PRODUCED COMMERCIALLY FOR USE PRIMARILY IN SUPERCONDUCTING SUPLEX COLLIDER (SSC) DIPOLES AND QUADRUPOLES. IN THESE IMPROVED MATERIALS, HOWEVER, LIMITATIONS TO THE EFFECTIVE FILAMENT SIZE AND OBSTACLES TO THE FURTHER INCREASE OF JC HAVE APPEARED. ONE OF THE MOST URGENT AND OBVIOUS OF THESE IS FILAMENT COUPLING. OTHERS ARE STABILITY, LONG UNIT LENGTH, FABRICABILITY, AND COST. THIS PROPOSAL IS TO INVESTIGATE THE LIMITATIONS IMPOSED ON THE CONDUCTOR DESIGN AND COST BY THE COMPETITION BETWEEN THE ELECTRICAL REQUIREMENTS AND THE MECHANICAL PROPERTIES OF THE COMPOSITE.PHASE I WILL ADDRESS VARIOUS WAYS OF REDUCING COUPLING WITHOUT COMPROMISING ON THE PROPERTIES OF THE COMPOSITE. PHASE 2 WILL ADDRESS THE LIMITING FACTORS MORE BROADLY, ATTEMPT TO DETERMINE THEIR RELATIVE IMPORTANCE, MODIFY THE CONDUCTOR DESIGN AND DEVELOP LOWER COST FABRICATION PROCEDURES.