Strain Mapping Using Electron Backscatter Diffraction
In this chapter we review the progress that has been made toward elastic strain (i.e., stress) mapping using electron backscatter diffraction. In particular we focus on development of an analysis method based on using cross-correlation to determine small shifts in the EBSD patterns with respect to a reference pattern. The pattern shifts are determined at many subregions dispersed across the wide angular span of the EBSD pattern, and the magnitude and angular distribution of shifts allows the strain and rotation tensor to be determined. Pattern shifts at a resolution of ±0.05 pixels, or in some cases even better, have been reported, which corresponds to a sensitivity of ∼±10–4 in the components of the strain and rotation tensor.
KeywordsStrain Gradient Angular Error Reference Pattern Pattern Shift Rotation Tensor
The authors are grateful to Dr. Mark Vaudin (NIST), Mr. Teruki Ishido (Matsushita Electric Industrial Co.), Dr. Cathy Vartulli (Texas Instruments), Mr. Benjamin Britton (Oxford University), Mr. David Randman (Oxford University), and Dr. Eleanor Clarke (Oxford University) for enjoyable and insightful discussion during development and application of this technique.
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