Two-dimensional misorientation mapping by rocking dark-field transmission electron microscopy

Area of Science:

• Materials Science
• Crystallography
• Electron Microscopy

Background:

• Accurate crystallographic orientation mapping is crucial for understanding material properties.
• Existing methods for orientation determination have limitations in precision and automation.

Purpose of the Study:

• To introduce a novel, automated approach for precise orientation mapping of crystalline specimens.
• To enable reconstruction of local orientation values from transmission electron microscopy data.

Main Methods:

• Utilizes dark-field image data acquired at varying specimen tilts.
• Employs multiple Bragg reflections for orientation reconstruction.
• Includes automated data acquisition and processing.

Main Results:

• Successfully reconstructed local orientation values from experimental data.
• Demonstrated the ability to determine the orientation of the tilt axis.
• Applied the technique to a Ni-based super-alloy (CMSX-4).

Conclusions:

• The developed method offers precise orientation mapping capabilities.
• The approach is automated, facilitating efficient data acquisition and analysis.
• Functionality and limitations were assessed and compared to existing techniques.