High-resolution 3D X-ray diffraction microscopy: 3D mapping of deformed metal microstructures.

Area of Science:

• Materials Science
• Crystallography
• Microscopy

Background:

• Three-dimensional X-ray diffraction microscopy (3DXRD) is established for bulk polycrystal analysis.
• Current 3DXRD methods have limited spatial resolution (∼1.5-3 µm).
• Analyzing submicrometre crystallites in deformed metals requires higher resolution.

Purpose of the Study:

• To present a high-resolution 3DXRD (HR-3DXRD) modality.
• To enable 3D mapping of submicrometre-sized crystallites or subgrains.
• To visualize metal microstructures at industrially relevant plastic deformation levels.

Main Methods:

• Developed HR-3DXRD by positioning a high-resolution detector between near-field and far-field regimes.
• Utilized intrinsic crystallographic properties for high-resolution imaging.
• Determined subgrain center of mass and volume for 3D mapping via tessellation.

Main Results:

• HR-3DXRD achieves submicrometre spatial and high angular resolution.
• Simulations demonstrated HR-3DXRD on realistic phantoms.
• Accurate retrieval of 772 out of 828 subgrains in deformed α-Fe (0.1 µm spatial, 0.0005° orientation accuracy).

Conclusions:

• HR-3DXRD significantly enhances 3D mapping capabilities for submicrometre microstructures.
• The technique is suitable for analyzing highly deformed metals.
• HR-3DXRD offers a powerful tool for materials characterization at the submicrometre scale.