Regensburg 2022 – wissenschaftliches Programm

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MM: Fachverband Metall- und Materialphysik

MM 3: Microstructures and Phase Transformations: Metals & Alloys

MM 3.1: Vortrag

Montag, 5. September 2022, 10:15–10:30, H45

Analysis of the precipitates in rapidly quenched Al-Cu alloys obtained in a magnetic pulse weld and through a melt spinning process — •David Stein, Maximilian Gnedel, and Ferdinand Haider — Universität Augsburg, Institut für Physik, Universitätsstraße 1, 86159 Augsburg, Germany

Magnetic pulse welding (MPW) is a collision welding technique, where a flyer is accelerated towards a target using induced magnetic fields. This technique enables the welding of dissimilar metals. The microstructure of the interface is well described in the literature and typically displays a wave like structure. In the eye and wake of these waves an area of intermetallic phases can be found, depending on the materials and welding parameters. In this case an Al 1050 flyer and Cu DHP target were used. The structure of the interface has given strong indications of melting. Atomic resolution HAADF STEM was performed on this part and GP I and GP II Zones and disc shaped Θ' phases were found in the same area. The latter typically only form after longer heat treatments at elevated temperature. Albeit the theoretically predicted shape of Θ' Phases is disc shaped with very large diameter to thickness ratio, in the case studied here, they are much more compact and have a far smaller diameter to thickness ratio. The current working hypothesis is, that in the MPW process rapid solidification of the melt occurs, which leads to a high density of excess vacancies in the crystal structure, allowing for higher atom mobility. In an ongoing study we follow the precipitation process in rapidly quenched Al-Cu alloys obtained through a melt spinning process.