| Title |
Surface Analysis of Features Seen on Nb3Sn Sample Coupons Grown by Vapour Diffusion |
| Authors |
- D.L. Hall, M. Liepe, J.T. Maniscalco, R.D. Porter
Cornell University (CLASSE), Cornell Laboratory for Accelerator-Based Sciences and Education, Ithaca, New York, USA
- T. Arias, P. Cueva, D.A. Muller, N. Sitaraman
Cornell University, Ithaca, New York, USA
|
| Abstract |
As a high-kappa superconductor with a coherence length of 7 nm, the superconductor Nb3Sn is highly susceptible to material features at the sub-micron scale. For niobium surfaces coated with a thin layer of Nb3Sn using the vapour diffusion method, the polycrystalline nature of the film grown lends to the possibility that performance-degrading non-uniformities may develop. In particular, regions of insufficiently thick coating and tin-depletion have been seen to occur in sample coupons. In the interests of understanding how to control the presence and nature of such features, it is necessary to know how they form. In this paper we stop the coating at defined instances to gain a stop-motion image of the growth of the layer, and use SEM and TEM techniques to image the development of the features seen in previously coated samples. We demonstrate that surface pre-anodisation can suppress the formation of thin film regions, and apply this technique to a single-cell cavity. Contemporarily, we use TEM with EDS mapping to monitor grain boundaries and tin-depleted regions within the layer.
|
| Paper |
download MOPVA119.PDF [1.655 MB / 4 pages] |
| Export |
download ※ BibTeX
※ LaTeX
※ Text/Word
※ RIS
※ EndNote |
| Conference |
IPAC2017, Copenhagen, Denmark |
| Series |
International Particle Accelerator Conference (8th) |
| Proceedings |
Link to full IPAC2017 Proccedings |
| Session |
Posters Monday 3 |
| Date |
15-May-17 16:00–18:00 |
| Main Classification |
07 Accelerator Technology |
| Sub Classification |
T07 Superconducting RF |
| Keywords |
niobium, SRF, simulation, cavity, site |
| Publisher |
JACoW, Geneva, Switzerland |
| Editors |
Volker RW Schaa (GSI, Darmstadt, Germany); Gianluigi Arduini (CERN, Geneva, Switzerland); Juliana Pranke (ESS, Lund, Sweden); Mike Seidel (PSI, Villigen, Switzerland); Mats Lindroos (ESS, Lund, Sweden) |
| ISBN |
978-3-95450-182-3 |
| Published |
May 2017 |
| Copyright |
|
