Correlated 4D-STEM and EDS for the classification of fine Beta-precipitates in aluminum alloy AA 6063-T6

• Published in: Scripta materialia Vol. 253; no. C; p. 116288
• Main Authors: Vogl, L.M., Schweizer, P., Donohue, J., Minor, A.M.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Ltd 01.12.2024; Elsevier
• Subjects: Energy dispersive X-ray spectroscopy (EDXS); Metals and alloys; Scanning/transmission electron microscopy (STEM); Metals and alloys; Scanning/transmission electron microscopy (STEM); Energy dispersive X-ray spectroscopy (EDXS)
• ISSN: 1359-6462
• DOI: 10.1016/j.scriptamat.2024.116288

Tuning the properties of aluminum alloys AA 6063-T6 involves artificial aging to induce precipitate formation, particularly β’’ and β’ phases. Previous characterization challenges due to their similar appearance are addressed here by correlating 4D scanning transmission electron microscopy (4DSTEM) and energy-dispersive spectroscopy (EDS) mapping. This approach allows us to analyze the structure and composition of precipitates individually, overcoming limitations of conventional imaging and structural analysis techniques when the precipitates appear simultaneously, as is often the case. We present detailed characterizations of needle-shaped Beta precipitates, revealing distinct diffraction patterns (DPs) and compositional differences. The method's applicability extends beyond aluminum alloys, offering a promising strategy for complex composite material characterization with multimodal scanning transmission electron microscopy (STEM) techniques. [Display omitted]