Structures and Moessbauer spectra of splat-cooled Al-Fe alloys

Structures of splat-cooled Al-Fe alloys were studied by transmission electron microscopy and the Mössbauer spectrocopy. Three types of structures were observed; globular, lamellar and eutectic phase free structures. The globular structure was prevalent in thick areas (>1μ), while the lamellar structures occupied thin areas between two globular structures. The area free from the eutectic phase occurred near the edge of the foil, where the thickness was less than the cell size. The mechanisms of the formation of these structures was discussed from the microstructural observation. Fe segregated in cell walls of the globular structure as fine particles. From the Mössbauer spectra, it appeared that the phase was solid solution iron.