Optimization of Ultrasonic Metal Welding Process Parameters for Copper Wire with Aluminium Sheet Using Taguchi Method and Finite Element Modeling of Stress Distribution

Ultrasonic welding is one of the advanced technologies in joining of non-ferrous metals. In ultrasonic welding dominating mechanism is solid state bonding, and it is accomplished by slip and plastic deformation. Aluminium sheet welded with copper wire has wide applications in automobile, electrical and electronics industries. Ultrasonic welding is used to join the workpiece in less time without addition of filler material resulting in high quality weld. This study is being carried out to understand the mechanism of ultrasonic metal welding and to optimize the process parameters like clamping pressure, weld time and amplitude for Al-Cu joint by Design of Experiment (DOE) using Taguchi method approach to maximize the weld strength. The parameters which affect the weld strength are identified based on the literature survey. Experiments are conducted for 0.2 mm thick aluminium specimen with 1.2 mm diameter copper wire and the strength of weld for all experiments are observed using computerized tensile testing machine. The Finite Element Modeling (FEM) is developed for predicting the stress distribution between the weld specimens during welding. Results obtained from experimental work and finite element model are discussed. The results are found to be in good agreement.