Investigation on the Mechanical Properties of Various Welded Materials by Ultrasonic Welding Technique – A Review

The use of diverse material combinations in engineering structures is witnessing growing interest, particularly in sectors such as transportation, due to the improvements it offers in design efficiency and overall performance compared to single-component materials. Ultrasonic welding (USW) is a promising modern technique for joining thin sheets of similar and dissimilar non-ferrous metals, such as aluminum and copper, without the need for fillers. This study analyses the effect of using a zinc intermediate layer on the development of the microstructure and mechanical properties of dissimilar aluminum/copper joints resulting from ultrasonic spot welding. This study focuses on the mechanical properties of asymmetric aluminum-copper joints created using ultrasonic welding. These joints typically exhibit high strength and resistance to various mechanical loads and stresses. Recent studies have investigated the relationship between the tensile strength of welded joints and key operating parameters, such as welding pressure, welding time, and fixation period. The results show that increasing the welding pressure while extending the process time enhances the bond strength between the welded plates. Furthermore, the use of intermediate layers, particularly zinc layers, has been shown to effectively improve mechanical performance by increasing the tensile and shear strength of the joints. The shear strength of ultrasonically welded aluminium/copper joints, both with and without zinc interlayers, initially increased by 35%, while fracture energy decreased threefold during the formation of the aluminium-zinc/copper-zinc phase. However, it declined when subjected to an input energy of 1000 J. Additionally, this review article systematically examines the mechanical behaviour of ultrasonic-welded sheets, interface characteristics, performance outcomes, and the influence of system parameters applies on a selected material combination.