Comparison between diffraction contrast tomography and high-energy diffraction microscopy on a slightly deformed...

Area of Science:

• Materials Science
• Crystallography
• Metallurgy

Background:

• Accurate reconstruction of grain structure is vital for understanding material properties.
• Diffraction contrast tomography (DCT) and high-energy diffraction microscopy (HEDM) are advanced techniques for microstructure analysis.

Purpose of the Study:

• To compare the capabilities of DCT and HEDM in reconstructing the grain structure of a deformed Al-Mn alloy.
• To assess the accuracy of both techniques in determining grain orientations, shapes, and volumes.

Main Methods:

• Reconstruction of grain structure using DCT and HEDM on an Al-0.3 wt%Mn alloy deformed to 1% strain.
• Acquisition of 14 HEDM layers and precise localization within the DCT volume using a generic algorithm.
• Comparison of microstructural features, including mean crystal orientations and grain shapes.

Main Results:

• DCT successfully detected subgrain boundaries with misorientations as low as 1°.
• Average distance between HEDM and DCT identified grain boundaries was approximately 4 µm.
• A relative deviation of about ≤10% in grain volume determination was observed between the two techniques for a polycrystal with ~100 µm average grain size.

Conclusions:

• DCT and HEDM provide comparable results for grain structure reconstruction, with DCT offering higher resolution for subgrain boundaries.
• The findings are significant for studies requiring precise grain volume measurements.
• Both techniques are valuable tools for advanced materials characterization.