Author/Authors :
Claus، نويسنده , , Hans-Jürgen and Borchardt، نويسنده , , Günter and Weber، نويسنده , , Sylvain and Hiver، نويسنده , , Jean-Marie and Scherrer، نويسنده , , Stanislas، نويسنده ,
Abstract :
In the present work we demonstrate that electron back scattering pattern (EBSP) measurements together with secondary ion mass spectrometry (SIMS) can be used to study the crystallographic orientation dependence of tracer diffusivities in polycrystalline materials. The crystal orientation of single grains was determined with a dedicated scanning electron microscope in the EBSP mode. 18O isotope depth profiles obtained in a subsequent tracer diffusion experiment were measured by SIMS on single grains with known orientation. The experiments yielded oxygen tracer diffusivities as a function of crystal orientation, temperature and strontium concentration for La2 − xSrxCuO4 ± δ (x = 0 and 0.15) between 600 and 900 °C. A strong anisotropy of the oxygen diffusivity for the investigated dopant concentrations was found.
Keywords :
diffusion , High-temperature superconductors , Electron back scattering patterns , Secondary ion mass spectrometry