Measurement and mapping of small changes of crystal orientation by electron backscattering diffraction

Area of Science:

• Materials Science
• Crystallography
• Electron Microscopy

Background:

• Conventional electron backscattering diffraction (EBSD) mapping struggles with accurately measuring minor orientation variations within grains.
• Indexing each point separately limits precision for subtle changes in crystal orientation.

Purpose of the Study:

• To develop and validate a novel EBSD-based method for quantifying small orientation changes within crystalline grains.
• To improve the precision of orientation measurements beyond conventional EBSD techniques.

Main Methods:

• Directly measuring shifts between successive EBSD patterns without individual indexing.
• Comparing the established zone axis shift method with a new Hough transform peak shift analysis.
• Utilizing the shift of Kikuchi bands in EBSD patterns for orientation change detection.

Main Results:

• The Hough transform method demonstrates superior accuracy for measuring orientation changes compared to zone axis tracking.
• The new method achieves a precision of approximately 0.1 mrad (0.006 degrees) in orientation measurement.
• This precision is attainable with standard EBSD configurations in a scanning electron microscope.

Conclusions:

• The developed EBSD analysis technique significantly enhances the ability to detect and quantify small orientation variations in materials.
• This method offers a more precise understanding of microstructural evolution and deformation mechanisms.
• The findings pave the way for more detailed crystallographic studies in materials science.