Characteristic Investigation of the As-Received Samples: Nano-Oxides in Al–5Mg–Be Melt

• Published in: International journal of metalcasting 2023-01, Vol.17 (1), p.334-341
• Main Authors: Akbarifar, Mehdi, Divandari, Mehdi, Boutorabi, Seyed Mohammad Ali, Ha, Seong-Ho, Yoon, Young-Ok, Kim, Shae-K.
• Format: Article
• Language: English
• Subjects: Characterization and Evaluation of Materials; Chemistry and Materials Science; Materials Science; Metallic Materials; Structural Materials; Technical Paper
• ISSN: 1939-5981; 2163-3193
• DOI: 10.1007/s40962-022-00773-1

Bi-films are double-layered oxide films entrapped in the casting parts. Characterization of such nano-sized defects has always been an engrossing issue. The oxide/Metal/Oxide (OMO) sandwich method provides a physical simulation of oxide layers with areas thin enough to be studied by High-Resolution Transmission Electron Microscopy (HRTEM). The effect of Be on the oxide composition on the surface of Al–5Mg melt was studied with the addition of 2000 ppm Be via OMO technique. The average thickness of the oxide films was measured to be 51.4 and 10 nm for Al–5Mg and Al–5Mg–Be samples, respectively. After EDS and XRD Investigations, the study was carried on with HRTEM equipped with Selective Area Electron Diffraction (SAED). OMO sandwich samples were susceptible to providing areas thin enough to be studied by HRTEM, with no need for sample preparation. While thermodynamics predicts the formation of MgO, BeO, MgAl 2 O 4 , BeAl 2 O 4 , and Al 2 O 3 oxides, SAED patterns only confirmed the formation of polycrystalline MgO and BeO layer in Be containing alloy.