Sn CONCENTRATION GRADIENTS IN POWDER-IN-TUBE SUPERCONDUCTORS

The Sn concentration gradients across the A15 phase have been studied by Energy Dispersive X-ray Spectroscopy (EDS) measurements. High spatial resolution EDS measurements in the Transmission Electron Microscope reveal a comparatively strong Sn concentration gradient from the periphery towards the centre of individual (Nb-Ta)3Sn grains.

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