Pre-industrial PIT conductor and coil development at Alcatel

Abstract

In 1.995 the PIT conductor development was strengthened at Alcatel and important progress has been achieved since. During 1997 the patented rectangular Alcatel route was upscaled and pre-industrial conductors have been fabricated in a wire drawing mill. After the successful transfer the first high performance conductors have been realized in kilometer lengths. The conductors are realized in cooperation with Aventis Research & Technologies using precursor powders optimized for the Alcatel conductor route. The simpler Bi3212/AgPd matrix conductor is used as a working horse where engineering current densities of Je = 65 kA/cm2 have been reached at 4 K, 0 T. Significant progress has also been achieved on Bi-2223 conductors where critical current densities of J c = 3 0 kA/cm2 at 77 K, OT are reached. First solenoids generating a field up to 2.3 Tesla have been realized using Bi-2212 conductors. In a background field of 3 Tesla this magnet still generates a field of 2 Tesla. The results on test coils are consistent with Jc(H) measurements on short samples showing that an important step towards high homogeneity conductors has been achieved.

Long length PIT conductors realized by rectangular deformation route

“…Green conductors have been used for realizing several W&R test coils using a novel NiO-insulating technology (Herrmann et al 1999). For ac conductors where a controlled twisting and de-coupling of filaments is necessary (Février et al 1989), it has been shown previously (Herrmann et al 1997) that square shaped conductors are more easily twisted down to low twist pitch values. Although some approaches exist for the de-coupling of filaments in PIT conductors (Goldacker et al 1999), there exists today no entirely satisfying conductor concept for ac applications.…”

Novel Cryogenic Engineering Solutions for the New Australian Research Reactor Opal

“…This temperature was selected as the best balance between performance of the cryocoolers (which decrease rapidly from around 14W at 20K to 1.5W at 4K) and the increase in critical current density that is achieved in the HTS magnets between 110K and 4K. Above 20K the critical current begins to rapidly drop [18]. To minimise heat being conducted from outside the magnet down to the BSCCO coils the conductor leads change from copper to BSCCO at a point in the magnet thermally connected to the first stage of the pulse tube cryocooler [19].…”