Nb/sub 3/Al strand processing, transport properties, and cabling

Nb/sub 3/Al strands with four different designs have been processed and tested. Strand specifications and some generic aspects of strand fabrication, processing, and testing are described. One strand type was long-length RHQT processed and transport tested at various lengths. Transport J/sub c/ results for short samples and small solenoid coils are presented and discussed for various RHQT protocols. Critical current measurements on various strands have been performed in fields from 18 to 26 T. Various strand stabilization techniques have been investigated including electroplating, plasma spray coating, and direct Nb-Cu high temperature diffusion bonding; these results are described. Fifty meters of strand was RHQ processed and then cabled into a short length of experimental 12-strand Nb/sub 3/Al Rutherford cable in preparation for transformation (T) and testing. Cabling properties are described.

[1]  M. Sumption,et al.  Processing-superconducting property correlation studies in RHQT-processed Niobium-Aluminum superconductors , 2002 .

[2]  M. Sumption,et al.  Development of multifilament jelly-roll NbAl precursor for melt-quench processing , 2002 .

[3]  M. Sumption,et al.  Phase formation during the rapid-heating step of RHQT Nb3Al superconductor processing , 2002 .

[4]  A. Shikov,et al.  High strength, high conductivity Cu–Nb based conductors with nanoscaled microstructure , 2001 .

[5]  M. Tomsic,et al.  Optimization studies for processing Nb/sub 3/Al by a rapid ohmic-heating and quenching method , 2001 .

[6]  K. Inoue,et al.  Nb/sub 3/Al conductor fabricated by DRHQ (Double Rapidly-Heating/Quenching) process , 2001 .

[7]  K. Inoue,et al.  Microstructures of rapidly-heated/quenched and transformed Nb/sub 3/Al multifilamentary superconducting wires , 2001 .

[8]  T. Takeuchi.  Nb3Al conductors for high-field applications , 2000 .

[9]  H. Wada,et al.  Field and temperature dependences of critical current density in rapid quenched and transformed Nb/sub 3/Al multifilamentary conductors , 2000, IEEE Transactions on Applied Superconductivity.

[10]  M. Tomsic,et al.  Process development and microstructures of Nb/sub 3/Al precursor strand for reel-to-reel production , 1999, IEEE Transactions on Applied Superconductivity.

[11]  M. Tomsic,et al.  Short-sample quenching of Nb/sub 3/Al precursor strand in support of reel-to-reel process development , 1999, IEEE Transactions on Applied Superconductivity.

[12]  C. Thieme,et al.  Nb/sub 3/Al wire produced by powder metallurgy and rapid quenching from high temperatures , 1989 .

[13]  R. Flükiger,et al.  A New metallurgical investigation of the niobium-aluminium system , 1980 .

[14]  M. Ricci,et al.  Practical Nb 3 Al wires: Experimental behaviour of small scale solenoids , 1979 .