Projekt

Process analysis of metal ultrasonic welding by sound emission

Ultrasonic Metal Welding of thin metal sheets is often used in the production of Lithium batteries, used in high numbers in electric cars for example. However, the current state of welding suffers from fluctuations in the weld strength which are hard to predict and control, even when using the same welding parameters. The goal of this project is twofold. On one hand, the goal is to improve the weld strength by investigating the welding process, based on vibrations of the welding machine and on the sound radiated during welding. On the other hand, the goal is to improve the inline quality control and monitoring of the welds, to improve the automation of the process.
The vibrations of the machine are investigated using laser Doppler vibrometer measurements and high-speed camera recordings, while the airborne sound radiation is investigated using experimental microphone recordings and simulations. Furthermore, measurements of the temperature changes during welding are taken into account.
Based on the experimental and simulation data, a better understanding of the welding process will be achieved, and guidelines for monitoring the ultrasonic metal welding of thin metal sheets will be suggested.