Muzzi L.,EURATOMENEA Association for Fusion |
Corato V.,EURATOMENEA Association for Fusion |
Della Corte A.,EURATOMENEA Association for Fusion |
De Marzi G.,EURATOMENEA Association for Fusion |
And 9 more authors.
Superconductor Science and Technology | Year: 2012
With the aim of clarifying the relationship between lattice deformations and superconducting properties of Nb 3Sn technological wires we have carried out high-energy x-ray diffraction experiments at the European Synchrotron Radiation Facility (ESRF) in Grenoble on individual samples of multi-filamentary internal-tin-type Nb 3Sn wires. In particular, a test probe developed at the University of Geneva allowed us to perform these experiments at 4.2K, while applying an axial tensile load to the specimen. In this way, the lattice parameter values of all the constituents (Nb 3Sn, Nb, Cu) were determined, in both the parallel and orthogonal directions with respect to the applied load axis, as a function of the applied strain. The experiments were performed on industrial wires, which were reinforced by a stainless steel outer tube, applied before the Nb 3Sn reaction heat treatment, in order to evaluate the effect of an additional pre-compression strain. The relation between the microscopically determined crystalline lattice deformations and the measured applied strain is discussed as a basis for the analysis of the superconducting performances of Nb 3Sn wires subject to mechanical loads. © 2012 IOP Publishing Ltd.