Model Quadrupoles TQ Shlomo Caspi LBNL DOE Review

Model Quadrupoles TQ Shlomo Caspi LBNL DOE Review FNAL July 15 -16, 2010 S. Caspi, LBNL

Outline • • Targets Status Lessons learned Summary LARP DOE REVIEW, FNAL July 15 -16, 2010 S. Caspi, LBNL 2

LARP – TQ Model Magnet Program Magnet Goals: § Demonstrate that Nb 3 Sn technology is a viable option for the LHC upgrade. TQ -Technology Quad Goals: § Maintain and develop Nb 3 Sn technology in US Labs § Demonstrate that a 200 T/m gradient can be reached in a 90 mm bore LARP DOE REVIEW, FNAL July 15 -16, 2010 S. Caspi, LBNL 3

Collaboration • BNL – Coil reaction and impregnation, conductor testing • FNAL – Magnet design and analysis, conductor testing, coil parts design and fabrication, coil winding, curing, reaction, impregnation, instrumentation, assembly, testing. • LBNL – Magnet design and analysis, conductor testing, coil winding, curing, reaction, impregnation, instrumentation, assembly and testing. • CERN – Magnet assembly and testing LARP DOE REVIEW, FNAL July 15 -16, 2010 S. Caspi, LBNL 4

TQ Parameters TQ Coil aperture mm 90 Overall magnet diameter mm 500 A/mm 2 3000 Maximum gradient 4. 4 K/1. 9 K T/m 239/262 Maximum current 4. 4 K/1. 9 K k. A 13. 6/14. 9 T 12. 25/13. 4 Jc 12 T, 4. 2 K, RRP 54/61 or 108/127 Peak field 4. 4 K/1. 9 K LARP DOE REVIEW, FNAL July 15 -16, 2010 S. Caspi, LBNL 5

TQ Technology Quadrupole – TQS, TQC TQS TQC LARP DOE REVIEW, FNAL July 15 -16, 2010 S. Caspi, LBNL 6

The TQ Program The TQ program has been the longest LARP magnet program (since 2004) and is now virtually completed. The program built a total of 33 coils 4 of which were practice coils (12%), 5 had issues (15%) and 24 (73%) were working coils. There were total of 17 tests, 5 (~1/3) were with virgin coils and 12 (~2/3) were with replaced or reused coils. The completed program has coils and 2 different structures that can still be used in the future. The TQC structure is at FNAL and the TQS structure is at CERN. LARP DOE REVIEW, FNAL July 15 -16, 2010 S. Caspi, LBNL 7

Lesson learned - Conductor • Magnet performance using Nb 3 Sn conductor with 54/61 filaments was unstable below ~ 2. 5 K (quench current at 4. 4 K is higher than 1. 9 K) Current (A) • Replacing the 54/61 conductor with 108/127 filaments magnet performance remained stable down to 1. 9 K 13500 13000 12500 12000 11500 11000 10500 10000 1, 9 2, 1 2, 3 2, 5 2, 7 2, 9 3, 1 3, 3 3, 5 3, 7 3, 9 4, 1 4, 3 4, 5 Temperature (K) LARP DOE REVIEW, FNAL July 15 -16, 2010 S. Caspi, LBNL 8

Nb 3 Sn Technology – Winding, Reaction and Impregnation Reaction Tooling Coil Winding Reaction Tooling Post Reaction: Nb. Ti Leads, VT, SG. Impregnation Tooling LARP DOE REVIEW, FNAL July 15 -16, 2010 S. Caspi, LBNL 9

Lesson learned – assembly • Applied force is provided by an outer shell or skin (not collars) • Assembly and coil compression is a delicate operation with a sensitivity of ~32 MPa/100 microns of displacement. • Key and bladder technology or a split and bolted outer skin is a way to control pre-stress (not welding) LARP DOE REVIEW, FNAL July 15 -16, 2010 S. Caspi, LBNL 10

Magnet Training Low/No retraining LARP DOE REVIEW, FNAL July 15 -16, 2010 S. Caspi, LBNL 11

Lesson learned – Pre-stress • 150 MPa is not a hard limit for magnet performance. • Impact of pre-stress on current plateau not too sensitive to stress. LARP DOE REVIEW, FNAL July 15 -16, 2010 S. Caspi, LBNL 12

Lesson learned – Magnet Performance … Increased pre-stress from 120 MPa to 160 Mpa LARP DOE REVIEW, FNAL July 15 -16, 2010 S. Caspi, LBNL 13

Lesson learned – Magnet Performance … • No degradation up to 1000 cycles 6000 A-11000 A LARP DOE REVIEW, FNAL July 15 -16, 2010 0 – 450 µε (70 -0 Mpa) S. Caspi, LBNL 14

TQ Summary § Maintained and developed Nb 3 Sn technology in US Labs Ø Nb 3 Sn technology - winding, curing, impregnation, instrumentation, protection. § 200 T/m gradient can be reached in a 90 mm bore ØTQ exceeded 200 T/m goal ( 237 T/m at 1. 9 K) • RRP 54/61 [Jc (12 T, 4. 2 K) 2925 -2950 A/mm 2] , unstable below 3 K • RRP 108/127 [Jc (12 T, 4. 2 K) 2925 -2950 A/mm 2], stable down to 1. 9 K Above Jc measurements are with self field correction (they are ~7% less without correction) • • Pre-stress 195 Mpa, Iss~88% (TQS 03 c) Reduced training (< 5 quenches, TQS 03 a) No re-training (TQS 03 b/c/d) 1000 cycles 6 -11 k. A without a quench LARP DOE REVIEW, FNAL July 15 -16, 2010 S. Caspi, LBNL 15