Ultrasonic assisted simultaneous composite casting - A feasibility study

This article reports on the improvement of cohesive connections by ultrasound assistance during master forming. In an attempt to produce monolithic components of several metals by simultaneous composite casting quality of the resulting bond between the metals was insufficient. Impurities and oxide layers on the metal surface were determined as the reason for bad bonding. In order to achieve an improvement the authors proposed ultrasonic excitation of the separating metal plate, in order to clean the plate´s surface by occurring cavitation. To verify the effect of such excitation, a feasibility study was carried out and the results are presented here. An ultrasonic transducer which provided an opportunity of mounting metal disks at its tip was developed and manufactured for these experiments. Aluminum was melted and the transducers tip with mounted metal disk, representing the separating plate, was dipped into the melt for a defined period of time. In the experiments the vibration amplitude of the ultrasonic excitation was varied. As a result an amplitude-dependent wetting improvement could be noted, which can even have a destructive effect on the samples.