28
Ternary
Nb-Ti-Ta
Alloys for High Field 2 K Applications--Alloy
Selection and Process Optimization--Global
Research and Development, Inc., 110 E. Canal Street, Troy, OH
45373; 937-332-0348
Dr.
Florin Buta, Principal Investigator, florin.buta@scientist.com
Mr.
Michael Tomsic, Business Official,
DOE
Grant No. DE-FG02-04ER83970
Amount:
$100,000
Even
before Nb3Sn dipole magnets are ready to come on line, particle
accelerators for high energy physics will require higher performance NbTi alloy
superconductors for operation above 8 tesla.
Although yielding excellent 5 T properties, the composition of
contemporary NbTi, as well as their associated precipitation heat treatments
(PHT), actually are optimal for high-field operation.
Furthermore, for high fields, even better performance is obtainable with
the Ta-substituted ternary alloy NbTiTa. This
project will demonstrate the exceptional high field properties of some NbTiTa
compositions. In Phase I, NbTiTa
alloys will be selected and melted, and monofilamentary NbTiTa/Cu composite
strands will be produced and heat treated (prior to the final cold deformations
stages) so as to optimize a-phase
precipitation (for flux pinning, hence Jc)
and b-matrix
composition (for Hc2).
In order to administer to the strand the usual “commercial” overall
strain during the overall diameter reduction, a cycle of Equal Channel Angle
Extrusion (strain without area reduction) will be inserted into the small-scale
process. Finally, the
superconducting properties will be verified.
Commercial
Applications and Other Benefits as described by the awardee:
High Energy Physics will be the primary beneficiary of this program.
The technology should lead to the production of higher performance
NbTi-base alloy superconductors for operation above 8 tesla, and to the
manufacture of superconducting cables for use in improved focusing quadrupoles
and the “low field” graded windings of higher field dipoles.