Numerical analysis of ultrasonic spot welding of metal sheets: a review

Ultrasonic spot welding has recently garnered significant attention as a method for joining metal sheets. Numerical simulation plays an important role in understanding the principles of this process and improving the quality of the ultrasonic spot welded joint. This paper aims to summarises the critical parameters in the finite element model of ultrasonic spot welding, including the friction coefficient, thermal field, acoustic and thermal softening, meshing and boundary conditions. Additionally, it provides a detailed review of the research status related to the simulation results, such as welding interface temperature, stress distribution, plastic strain, intermetallic compounds, macrostructure, dynamic recrystallisation and interfacial diffusion. Furthermore, this paper discusses the remaining challenges and the development trend of the numerical simulation.