Numerical Study on Stress Distribution in Ultrasonically Welded Electrical Contacts used in Automotives

Numerical stress analysis while joining an electrical contact comprising of copper wire and copper sheet using ultrasonic metal welding process is vital in many of the automotive applications. During ultrasonic metal welding, shear and normal force act at the interface between the welded specimens. These forces are the result of ultrasonic vibrations transmitted by Sonotrode onto the welded specimens. In this work, the distribution of the stress developed at the interface and the correlation of the developed stress with strength of joint are studied. The theoretical stress values are determined using various levels of ultrasonic metal welding process parameters such as clamping force, vibration amplitude and weld time to validate the results of stress obtained from finite element analysis. The results of stress from numerical analysis are found to be in good agreement with that of results obtained from the theoretical calculations.