Abstract

In this presentation we will briefly review earlier attempts to study local elastic and plastic strains distributions using EBSD before moving on to discuss recent cross-correlation based analysis of EBSD patterns. Cross-correlation methods can be used to determine small shifts in features within an EBSD pattern compared to a reference pattern. Pattern shift measurements at many regions of the patterns can be used to establish a best fit strain and rotation tensor. Shift measurements at ±0.05 pixels allow the elements of the strain tensor (and small misorientations) to be measured to ±10-4 (and ±0.006° for rotations). This is a significant improvement in the angular resolution compared to the conventional linear Hough (or Radon) transform based EBSD analysis. The new cross-correlation based analysis has been applied to several varied materials science problems. Results from functional (SiGe/Si mesa and GaN layers) and structural materials (crack tips, and nanoindentations) will be used to illustrate the use of the method in studying both elastic and plastic deformation.