AbstractThe ultrasonic welding technology enables to produce high‐strength joints between sheet metal and aluminium foam sandwich (AFS) without melting of the metal or any damage of the foam structure. In the investigations the used welding processes and different factors influencing the weldability were varied. The achievable mechanical properties for ultrasonically welded metal joints, especially under monotonic and cyclic load, will be discussed. Additionally, results of microscopic investigations of the bonding zone and possible applications are presented.