Application of Electron Backscatter Diffraction to Grain Boundaries

Abstract

The technique of electron backscatter diffraction (EBSD) is ideal for the characterisation of grain boundary networks in polycrystalline materials. In recent years the experimental methodology has evolved to meet the needs of the research community. For example, the capabilities of EBSD have been instrumental in driving forward the topic of ‘grain boundary engineering’. In this paper the current capabilities of EBSD for grain boundary characterisation will be reviewed and illustrated by examples. Topics are measurement strategies based on misorientation statistics, determination of grain boundary plane distributions and grain boundary network characteristics.

Direct estimation of austenitic grain dimensions in heat affected zones of a martensitic steel from EBSD images

“…Creep properties of P91 steel grade welds have been characterized using data obtained from cross weld samples (Vivier, ), and similar samples have been optically monitored during high‐temperature tensile experiments to identify viscoplasticity coefficients in several sections of the welds using digital image correlation (Touboul et al ., ). Those welds are prone to the so‐called type IV failure, which mainly occurs during creep in the fine‐grained heat‐affected zone (FGHAZ) or intercritical heat‐affected zone (ICHAZ) also having fine grains (Albert et al ., ), and that remains challenging to justify and predict from sole metallurgical features, such as grain boundaries properties (Randle, , ; Calcagnotto et al ., ). Despite the lack of microstructural explanations, finite element calculations with relevant contrast in mechanical properties have been successful to capture localization consistent with type IV failure at a macroscopic scale (Touboul et al ., ).…”