Design and fabrication of a 14 T, Nb/sub 3/Sn superconducting racetrack dipole magnet

Common coil magnet program at BNL

“…The Nb$n cable for the first three coils was provided by Lawrence Berkeley National Laboratory (LBNL) and is similar to the cable used in magnet RD2 [6] except that the critical current is 20% lower, based on extracted strand measurements at the University of Twente [9]. The cable uses 30 strands of chrome-plated 0.8 mm diameter wire and has a nominal width of 12.3 mm and thickness of 1.45 mm.…”

“…In Phase I of this program, a proof of principle 6 T, NbTi dipole was built and commissioned [5] at BNL. Magnets based on the common coil design have also been built at Lawrence Berkeley National Laboratory [6,7]. Another is in the advanced design stage at the Fermi National Accelerator Laboratory [g].…”

A new support structure for high field magnets

“…Unfortunately, high field involves large forces and requires higher pre-stress. For the foreseeable future, Nb 3 Sn is the only practical high-field conductor available. The combination of large forces and brittle conductor makes the design and assembly of such magnets a real challenge (Fig.…”

Common coil magnet system for VLHC

“…The viability of the common coil design has been demonstrated in a Nb,Sn 6 T magnet that was tested recently at LBNL and reached the cable short sample field without any training quenches [7]. The mechanical design work is now underway to develop a structure for a 14-15 T dipole [8].…”

“…In addition to the cosine theta designs [5], the other design approaches can be broadly divided in two categories. The low field design based on the low cost transmission line iron dominated magnet that is being pursued at FNAL [6] and the high field design based on a common coil geometry that is being pursued at LBNL [7,8] and BNL [9].…”