Effect of subelement spacing in RRP Nb3Sn strands

Conference · Mon Oct 01 04:00:00 EDT 2007

OSTI ID:919076

Barzi, E; Turrioni, D; Alsharo'a, M; Field, M; Hong, S; Parrell, J; Yamada, R; Zhang, Y; Zlobin, A

The Restacked Rod Process (RRP) is the Nb{sub 3}Sn strand technology presently producing the largest critical current densities at 4.2 K and 12 T. However, when subject to plastic deformation, RRP subelements (SE) were found to merge into each other, creating larger filaments with a somewhat continuous barrier. In this case, the strand sees a larger effective filament size, d{sub eff}, and its instability can dramatically increase locally leading to cable quench. To reduce and possibly eliminate this effect, Oxford Instruments Superconducting Technology (OST) developed for FNAL a modified RRP strand design with larger Cu spacing between SE's arranged in a 60/61 array. Strand samples of this design with sizes from 0.7 to 1 mm were first evaluated for transport current properties. A comparison study was then performed between the regular 54/61 and the modified 60/61 design using 0.7 mm round and deformed strands. Finite element modeling of the deformed strands was also performed with ANSYS.

• Research Organization: Fermi National Accelerator Laboratory (FNAL), Batavia, IL
• Sponsoring Organization: USDOE
• DOE Contract Number: AC02-07CH11359
• OSTI ID: 919076
• Report Number(s): FERMILAB-CONF-07-398-TD
• Country of Publication: United States
• Language: English

Related Subjects

43 PARTICLE ACCELERATORS
Accelerators
CABLES
CRITICAL CURRENT
CRYOGENICS
DEFORMATION
DESIGN
INSTABILITY
NIOBIUM COMPOUNDS
PLASTICS
SIMULATION
TRANSPORT