HHHAMTRoad Map for European Conductor Conductor and Magnet

HHH-AMT-Road Map for European Conductor • Conductor and Magnet have to be developed in close and interactive loop. • If a conductor has a current density in the range 1000 -2000 A/mm 2 at field X and temperature Y, a magnet at max field X and at temperature Y can be built. • The bore diameter (which defines the stored energy, the forces, the protection) has to be defined as soon as possible to make models and prototypes( ~5 years ). • In DC magnets, beam losses have to be minimized by the optics scheme. No conductor in the horizontal plane (less efficiency of the Ampere-turns). • In AC magnets, the main load are the AC losses. Tools exist to calculate them. • The thermal load will define the temperature margin and then the operating field (20 m. W /cm 3 at 1. 9 K ) 12 -11 -04 HHH-AMT-D. Leroy-Road Map for European Conductor 1

HHH-AMT-Road Map for European Conductor • Nb. Ti at 1. 9 K 1200 A / mm 2 at 11 T Margin of 1. 5 K leads to Bq-1. 5 T Material well specified( Fe effect can be considered for micro structure improvement and jc increase w/o long heat treatments) Magnet construction known For AC applications, filaments of 3. 5 m in Cu matrix is feasible. Smaller filament size of 2 to 3. 5 m needs R&D ( matrix material) • Nb Ti Ta at 1. 9 K 1200 A / mm 2 at 12 T Material to be developed , needs R&D (2 to 3 years) Ta content and small grain size to be controlled Needs support(1. 5 M €)!!! 1 T increase has not to be neglected Magnet construction known 12 -11 -04 HHH-AMT-D. Leroy-Road Map for European Conductor 2

HHH-AMT-Road Map for European Conductor • Nb 3 Sn Needs R&D European goal : 1500 A /mm 2 at 15 T and 4. 2 K (NED in 2007) Very sensitive to tensile stress/strain: avoid bending moments in cables under magnetic forces. Should we aim to small strand diameter? Has a volumetric expansion of 27 % at reaction Magnets of length 5 to 10 m to be developed (~ 8 years? ) in the route wind and react. • Nb 3 Al Less sensitive to stress/strain. Has the potential to be used in the route react and wind. Developments very slow. Main interest for MR in Japon 12 -11 -04 HHH-AMT-D. Leroy-Road Map for European Conductor 3

HHH-AMT-Road Map for European Conductor • Mg B 2 Critical Temperature of 30 K and Hc 2 of 30 T. Potential of a higher temperature margin. Critical current densities still too low. Less good superconducting properties in perpendicular field Mechanical properties to be measured, methodology to be developed for this hard powder. Ways for stabilization to be found. • High Tc Bi-SCCO 2212: 2000 A/mm 2 at 12 T (Showa/LBNL)-Flat Jc vs B-Cable exist Je~600 A/mm 2 (Nexans /OST). Significant improvement can be anticipated from optimizing conductor design, grain size and additives in Ag, overall composition, pre-annealing, melting and solidification steps of heat treatment. Engineering of heat treatments on coils to be developed. (1 M € on 4 years ) • Y-BCO 12 -11 -04 HHH-AMT-D. Leroy-Road Map for European Conductor 4

HHH-AMT-Road Map for European Conductor Strand diameter 1. 250 ± 0. 004 mm Effective Filament diameter according to billet design Copper to non-copper volume ratio 1. 25 ± 0. 10 Filament twist pitch after cabling Filament twist direction < 50. 0 µm 30 ± 3 mm right-handed screw Minimum critical current at 4. 222 K 1636 A at 12 T 818 A at 15 T RRR (after full reaction) n-value @ 15 T and 4. 2 K 12 -11 -04 HHH-AMT-D. Leroy-Road Map for European Conductor > 200 > 30 5

HHH-AMT-Road Map for European Conductor Cable width Cable mid-thickness at 50 MPa Keystone angle Cable thin edge thickness Cable thick edge thickness Cable transposition pitch Number of superconducting strands Critical current at 4. 222 K, with field normal to broad face 26 mm 2. 275 mm 0. 22 degrees 2. 175 mm 2. 375 mm ~180 mm 40 29440 A at 15 T 58880 A at 12 T Minimum critical current at 4. 222 K of extracted strand 736 A at 15 T 1472 A at 12 T n-value @ 15 T and 4. 222 K > 20 Residual resistance ratio before reaction ≥ 70 after reaction ≥ 120 Cable transposition direction Minimum unit length 12 -11 -04 left-handed screw thread 145 m HHH-AMT-D. Leroy-Road Map for European Conductor 6

HHH-AMT-Road Map for European Conductor July 2004 Contract signature Decembe r 2004 12 -11 -04 Progress report 1 June 2005 Qualification of initial strand designs 2 Decembe Qualification Fabrication/tests of at least 10 kg r 2005 of final of strand relevant cabling strand tests design Progress report 3 June 2006 4 Decembe Total cable r 2006 fabrication Total strand production Fabrication/tests of at least 10 kg of strand relevant cabling tests Progress report Fabrication/tests of total strand quantity and cabling tests Progress report Total cable quantity delivery Final report HHH-AMT-D. Leroy-Road Map for European Conductor 7