Crystallite size of pure tin oxide ceramics and its growth during sintering determined from XRD line broadening – A methodological case study and a practitioners’ guide

Abstract

Due to the dominance of non-densifying sintering mechanisms (surface diffusion and evaporation condensation) pure tin oxide ceramics exhibit unusual sintering behavior that allows sintering without shrinkage, i.e. without changes in porosity. It is therefore ideally suited for fundamental studies. In this paper we study the crystallite size and its changes as a function of temperature and dwell time via X-ray diffraction (XRD) line broadening. It is shown that, although the contribution of microstrain broadening is negligibly small, the difference between the different evaluation methods (Scherrer equation, Williamson-Hall plots, Halder-Wagner plot) is quite large. Nevertheless similar qualitative conclusions can be drawn irrespective of the specific evaluation method used (although Halder-Wagner analysis is most reasonable). Significant crystallite growth can be expected for pure tin oxide ceramics from nanosized powders only at temperatures above 1000 °C. Prolonging the dwell times beyond 3 h does not affect the crystallite size to any significant degree.