Mechanism and Influencing Factors of Frictional Energy Dissipation in Multilayer Ultrasonic Welding

Abstract

In multilayer ultrasonic welding, the sonotrode presses on metal sheets and drives the sheets to produce ultrasonic vibration. Then, each contact interface generates heat, produces plastic deformation, and forms solid-state bonding. However, the load distributes unevenly in each sheet, which results in the uneven friction state and inconsistent welding quality. Hence, it is necessary to reveal the mechanism of frictional state and energy dissipation based on the load distribution in each sheet. A finite element model of 5-layer copper sheets is established using Abaqus and considering the Cattaneo-Mindlin contact theory. The clamping force and ultrasonic vibration in each interface is simulated. The slip-stick state of each interface is obtained and the effect of the clamping force are analyzed. The frictional energy dissipation and proportion of each interface are calculated, the influencing factors of frictional energy dissipation are summarized, and the optimization of input clamping force is discovered, which can provide theoretical guidance for the improvement of multilayer ultrasonic welding.

Keywords

• ultrasonic welding
• multilayer friction
• slip-stick state
• frictional energy dissipation
• finite element method (fem)