Nuclear microprobe analysis of U-doped (Bi,Pb)(2)Sr2Ca2Cu3Oy/Ag superconducting tapes

作者：Rout B; Hendriks J; Jamieson DN^*; Szymanski R; Milliken D; Dou SX

来源：Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms , 2002, 190: 357-364.

DOI：10.1016/S0168-583X(01)01318-0

• HTC superconductor
• nuclear microprobe
• RBS
• PIXE

Superconducting (Bi,Pb)(2)Sr2Ca2Cu3Oy/Ag tapes are doped with uranium compounds to introduce flux pinning defects from neutron-induced fission. The composition and distribution of elements in cross sections of the tapes were probed with a scanned 3 MeV proton microbeam using proton induced X-ray emission (PIXE). Distributions of the constituent elements were found to be heterogeneous on a scale of 10 mum. By combining the PIXE analysis with Rutherford backscattering spectrometry, the stoichiometry of the superconductor within the tape was measured, including oxygen from elastic scattering, revealing a departure from the desired 2223 composition. In one of the tapes, PIXE elemental maps of the Ag distribution showed diffusion of Ag into the superconductor from the enclosing jacket. Crystals of the same material, not fabricated into tapes, did not contain the contaminants and had a more ideal stoichiometry. Correlation maps between the constituent elements, deduced from the elemental maps, indicate the presence of secondary or unreacted phases.

• 出版日期2002-5