A Novel Non-Destructive Probe for Rapid Grain Boundary Characterization on the Mesoscopic Scale—Lab-Based Diffraction Contrast Tomography

The grain boundary characters are essential information to analyze grain boundary related behaviors such as preferential precipitation or intergranular cracking in polycrystalline materials. Accessing the necessary parameters to describe a grain boundary on the mesoscopic scale is beyond the reach of 2D characterization techniques and is only achievable through a 3D approach. With the capability to map the grain morphology and crystallographic orientation non-destructively in 3D, lab-based diffraction contrast tomography (DCT) using X-rays provides the necessary information to analyze the crystallographic parameters describing grain boundaries on the mesoscopic scale, including grain boundary misorientation angle/axis and plane inclination. In this work, we will present the results of using lab-based DCT to investigate the grain boundary characters in polycrystalline materials including ceramic examples, with further discussion of how the grain boundary properties are related to grain boundary behaviors such as grain boundary wetting and cracking. Results further demonstrate how this technique can be extended for 4D studies and in-situ investigations of polycrystalline materials.