Using local GND density to study SCC initiation

On the role of intergranular nanocavities in long-term stress corrosion cracking of Alloy 690

“…This method is based on the method suggested by Wilkinson et al [29] and Pantleon [30] and built on the local dislocation density tensor introduced by Nye [31] . More details about its application to IGSCC can be found in [32] . Given the high level of deformation caused by the prior cold-work and the associated challenges choosing a suitable reference within a grain, the GND calculations in this work are not based on high-resolution cross-correlation but on a Hough-based indexing routine instead [33] .…”

Effect of sample thinning on strains and lattice rotations measured from Transmission Kikuchi diffraction in the SEM

“…This crosscorrelation approach (HR-TKD in this case), can be used to measure strain and rotation fields (thereby a GND density estimation for deformation) in small areas not accessible by traditional EBSD, via a site-specific FIB liftout or by electropolishing [22]. An example of the potential of this technique is for the study of localised deformation around crack tips (especially in stress corrosion cracking, where the cracks are sub-surface) [24,25] or around smaller microstructural features that need a high spatial resolution for imaging/measurement [26].…”