Shape Memory Assemblies Using Ultrasonic Welding

The paper describes the research developed in order to assemble shape memory alloys using welding technologies with the aim to reduce the heat affected zone. It is shown that ultrasonic welding can be solutions that could be considered for this purpose. Experiments on welding shape memory alloys have been performed on bulk and rapid solidified ribbons and the interface has been characterized using microstructural observations. The investigations show the difficulties in assembling microfabricated shape memory ribbons with conventional sonotrode/anvil solutions due to the limited thickness of the ribbons and the need to develop microstriations on the surface of the ultrasonic welding tools. It is however considered that ultrasonic welding can be a solution for joining shape memory alloys in similar or dissimilar architectures.