SMI : Status of contract

1
SMI Status of contract

• SMI completed the step 2 with the cabling test
  done at Berkeley end of June 2007.
• Cable samples characterized by metallographic
  examination and critical current measurements on
  extracted strands.
• Reasonable Ic degradation between 4 and 8
  obtained by comparing extracted strands and
  virgin strands.
• Following the acquisition of the PIT technology
  by EAS, total strand production for the NED cable
  will be done under the responsibility of EAS. EAS
  declined to take the responsibility of the
  cabling and the cabling cost will be deduced from
  the contract. The cabling will be done under
  CERNs responsibility.
• A contract amendment was signed in July with EAS
  for the delivery of 12.7 km of strands not later
  than February 2008.

2
Alstom Status of contract 1/2
Fabrication Status of step 2
Billet 1 Fabrication launched into
fabrication in 2006, a Jc of 1900 A/mm2 was
achieved at 12 T and 4.2 K. Many breakages during
drawing of the billet to final diameter.
Billet 2 Fabrication of the sub-elements
started in March 2007, the billet was stacked
with 114 sub-elements instead of 78. Many
breakages during drawing starting at a diameter
of 36 mm due to the sub-elements layout in which
few sub-elements were severely damaged during the
first drawing steps. A Jc of 1800 A/mm2 was
achieved at 12 T and 4.2 K.
Billet 3 Same sub-element as for billet 2
but with NbTa filaments. An improved arrangement
of the sub-elements in the final billet was
designed. A new set of drawing dies will be used
to improve the workability. The final billet will
be mounted with 78 sub-elements. Expected Jc
2500 A/mm2 at 12 T.
3
Alstom Status of contract 1/2
Billet 4 To solve the problems related to the
lack of cohesion, new sub-elements obtained by
warm extrusion were produced early 2007 and are
nearly ready for restacking. The billet will be
drawn with a new set of drawing dies to improve
the workability of the strand. An improved layout
of the sub-elements in the final billet will be
implemented. Completion of the drawing beginning
of December 2007.
4
Alstom Summary of status for step 2
Billet Cu/non Cu Number of sub-elements Completion date Goal
1 1 bis 1 ter 1.60 78 21/12/2006 Jc 1900 A/mm2 obtained on a strand of 1.25 mm and 2090 A/mm2 on a strand of 0.825 mm. Billet called B1-14508
2 1.60 78 Not fabricated very thin Cu tube for the sub-element
3 1.60 78 Drawing stopped NbTi billet with a thin Cu tube shaving of the sub-element billet
4 1.67 114 June 2007 Jc 1800 A/mm2 obtained B1-21204
5 1.60 78 Jan. 2008 Jc 2500 A/mm2 expected, NbTa filaments
6 1.60 78 Jan. 2008 Jc 2500 A/mm2 expected, Nb tube.
7a 7b 1.60 78 253 Dec. 2007 Jc 2500 A/mm2 expected Sub-elements produced by extrusion