3D reconstruction and characterization of polycrystalline microstructures using a FIB–SEM system

A novel methodology is described in this paper which is a step towards three-dimensional representation of grain structures for microstructure characterization and processing microstructural data for subsequent computational analysis. It facilitates evaluation of stereological parameters of grain structures from a series of two-dimensional (2D) electron backscatter diffraction (EBSD) maps. Crystallographic orientation maps of consecutive serial sections of a micron-size specimen are collected in an automated manner using a dual-beam focused ion beam–scanning electron microscope (FIB–SEM) outfitted with an EBSD system. Analysis of the serial-sectioning data is accomplished using a special purpose software program called “Micro-Imager”. Micro-Imager is able to output characterization parameters such as the distribution of grain size, number of neighboring grains, and grain orientation and misorientation for every 2D section. Some of these data can be compared with results from stereological exercises. Stacking the 2D statistical information obtained from the analysis of the serial-sectioning data provides a means to quantify the variability of grain structure in 3D.