New levels of high angular resolution EBSD performance via inverse compositional Gauss-Newton based digital image...

Area of Science:

• Materials Science
• Crystallography
• Electron Microscopy

Background:

• Conventional high angular resolution electron backscatter diffraction (HREBSD) relies on cross-correlation to analyze diffraction patterns.
• This method quantifies relative elastic strain and misorientation by tracking feature shifts.

Purpose of the Study:

• To adapt inverse compositional Gauss Newton (ICGN) digital image correlation (DIC) for HREBSD applications.
• To improve the accuracy of strain and misorientation measurements in HREBSD.

Main Methods:

• Developed an ICGN-based digital image correlation (DIC) technique compatible with HREBSD.
• ICGN-DIC efficiently tracks both feature shifts and shape changes in diffraction patterns.
• Applied and compared ICGN-based HREBSD against conventional cross-correlation HREBSD methods using simulated data.

Main Results:

• ICGN-based HREBSD demonstrated approximately half the strain error compared to the best cross-correlation HREBSD method.
• The computational time for ICGN-based HREBSD was comparable to conventional methods.
• Incorporating shape change modeling in HREBSD enhances measurement accuracy.

Conclusions:

• ICGN-based HREBSD offers a more accurate and efficient approach for analyzing material deformation.
• This advancement provides improved precision in quantifying elastic strain and misorientation in materials.