LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich LARP Cable R&D D.R. Dietderich LBNL

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Outline Status of cables for LARP – TQ –LR and SQ Critical current testing cables – At NHMFL with transverse pressure Loading at LHe temperatures – At CERN in the FRESCA facility (G. Ambrosio on Friday) Loading at room temperature

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Cable Fabrication

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich TQ Cable Parameters

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Minor Edge of 3 TQ Cables 928R 939R 940R Large edge facets on cable 939R

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Minor Edge of 939R & 940R 939R -- The two strand just in from the edge of the cable have at least 5 sheared sub-elements 940R -- The two strand just in from the edge of the cable are OK

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Cable Observations All three cables are in specification of thickness, width, and keystone angle Cable 939R –Has a very large facet on minor edge and sheared sub-elements –Two facets on major edge Cable 940R –Facets on major and minor edge are consistent with other TQ cables such as 928R.

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Why are the cables different? Its not clear why cables 939R and 940R are different –Different strand Ic at 12T of strand: 8220 (939R) is higher than 8647 (940R) –This suggest sub-elements with different composition »8220 may have more Sn Pitch Length different: 40mm vs. 14mm. –Anneal prior to re-rolling of cable may have been different Cable 939R was double the mass of 940R

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich New Procedures and Documention – Draft First cable pass – Stop after 3-5m Evaluate facets on edge of cable and cable parameters from CMM Mount sample for metallography and inspect sub-elements Place cable sample in achieves – Make necessary adjustments to Turks head and proceed with run Annealing of cable – Annealing conditions C for 2 h The annealing box will be purged with 40 cf of Argon prior to the anneal A thermocouple will be placed into the cable stack on the take-up spool to monitor cable temperature Second cable pass – Install 2 nd set of rolls 50 microns wider than those used in the first pass –Stop after 3-5m Evaluate facets on edge of cable and cable parameters from CMM Mount sample for metallography and inspect sub-elements – Make necessary adjustments to Turks head and proceed with run Samples – Take a sample for metallography – Ship 2.5m of cable to BNL and FNAL. – Evaluate cable If qualified then insulate and ship to Lab winding coils

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Developing Integrated Note to Become Traveler Will combine the following – Cover page will be the typical LBNL cable document –Cable specifications and requirements – Confirmation of inventory in strand map – Re-spooling procedure and re-spooling map –Cable run check list – Cable evaluation procedures before starting run – Heat treatment profile for the cable anneal –

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Possible Strand for TQ1a Conductor needed: 25kg minimum Jc (12T, 4.2K): 2,000-3,000A/mm 2 RRR: >50 Stability Current I s (4.2K): >650A Strand /91 stack

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Prototype TQ Cable with 90 Sub-elements Cable fabricate TQ style cable with Oxford RRP with with 90 sub-elements

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Sub-Scale Cable Parameters ItemValue Tolerance Number of strands20 NA Strand Diameter0.7 mm +/ mm Thickness1.276 mm +/ mm Width7.793 mm +/ mm Pitch Length54.0 mm +/- 3.0 mm

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Sub-Scale Cable Cable is rectangular and narrow Easy to make mechanically stable for magnet winding. Light deformation of strands at the edge Low risk of damaging strand

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich SM-01 Magnet Performance Cable 809 Strand ORe 143c Coils SC-01 and 02 RRR Coils very stable Achieved short sample

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Edge of Cable 926R for SQ-02 and Cable 935R for SR R MJR 935R MJR

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Stability Current (I s ) for Strand 8220 – Sub-scale and TQ type cables BNL & FNAL Data XS - Sub-Scale Cable Virgin Magnet Limit

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Critical Current (I c ) for Strand 8220 – Sub-scale and TQ type cables BNL & FNAL Data

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Performance of Cable 935R in Transformer Test Sub-scale cable 935R strand 8220 Data Normalized to Number of Strands FNAL Data

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Strand Data for LR cables – Billets 8647 and 8648 RRR 200 BNL data Cable 942R

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich LR Cable Production Cu dummy cable fabricated week of 4/3/2006 –Has been annealed –Needs to be re-rolled Production Runs: –First UL of Nb 3 Sn (billet 8647) cable fabricated week of 4/17/2006 Annealing and re-rolled week of 4/24/2006 –Second UL of Nb 3 Sn (billet 8648) cable will be fabricated in May 2006

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Cable Testing

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Performance of Cable 935R in Transformer Tests Sub-scale cable 935R strand 8220 Data Normalized to Number of Strands FNAL Data

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Transverse Pressure Measurements Single superconducting strand in a cable made of Cu wire Correlate to prototype magnet performance to determine if stress limiting Need to measure more cables under transverse pressure E. Barzi, FNAL

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Cross-Section of Samples NHMFL U. Twente Cable

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Sample and Magnet Orientation for Tests NHMFL Two Nb 3 Sn cables in 304 SS holder in radial access port Split pair solenoid

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich NHMFL Loading Piston and Bellows

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Loading Fixture in Magnet at NHMFL and Sample

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Sensitivity of Cable to Transverse Stress 11 T LBL Cable # 523 MJR-TWCA LBL Cable # 522 IGC-Int. Tin D-20 HD-1 RRP-Oxford NHMFL Test 150mm uniform field 122mm load length MJR recover Ic when unloaded Less Cu more Nb 3 Sn in subelement Nb 3 Sn filaments sinter together Stress Issue? B  Nb 3 Sn Cable + 

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Difference In Testing Facilities Twente Single U-shaped Cable – Current redistribution Load length only 40 mm – 90 mm cable pitch Difficult to guarantee uniform loading Regions outside of loading area may not be constrained Nb-Ti leads soldered directly to Nb 3 Sn Voltage taps soldered to individual strands NHMFL Two straight cables Load length 122 mm – 90 mm cable pitch Uniform loading due to beam configuration Sample constrained on all sides Solder box method developed for D20 Cu-Sn alloy foil developed for LBNL magnets

LARP Meeting April 2006LARP Magnet Program – D.R. Dietderich Summary  LR cable production  Cu dummy cable and NbTi leader material have been made  First UL is being evaluated  Second UL will be fabricated by the middle of June 2006  TQC-02 cable production  6 UL have been fabricated  4 UL did not pass evaluation  Therefore a new cable must be fabricated by the middle of June 2006  Cabling of strand with larger number of sub-elements is feasible  Still need to explore fabrication limits of cables with different keystone angles and widths  Transverse stress on cables: Need to perform full size cable tests to complement the strand tests now being performed