Ultrasonic Joining of Additively Manufactured Metal-Composite Hybrid Joints: A Comparison between Vertical and Horizontal Vibration Modes

Ultrasonic Joining (U-Joining) is a novel friction-based joining technique that produces through-the-thickness reinforced hybrid joints between surface-structured metals and thermoplastics. The process feasibility has been successfully demonstrated to join unreinforced or fiber-reinforced polymer parts by applying horizontal vibration. However, intense tool wear was observed for the explored combinations of materials, which could diminish mechanical performance produced hinder application. These investigations left an unexplored field regarding application different vibration modes, represent good solutions minimize reported. Therefore, present study aims explore vertical identify possible advantages disadvantages this variation. case-study combination additively manufactured 316L stainless steel 20%-short-carbon-fiber poly-ether-ether-ketone selected purpose. Initially, set optimized parameters obtained variation following one-factor-at-a-time approach. In previous study, were already mode, results used comparison purposes. Single-lap shear using both monitoring indicated reached lower energy input given time. tested, with achieved higher ultimate lap forces than ones ones: 3.6 ± 0.3 kN 1.6 kN, respectively. Microstructural at fractured surfaces showed difference due insufficient frictional heat generation metal-composite interface when applied. temperatures during cycle are not enough melt completely interface, preventing complete surface wetting metal reducing micromechanical interlocking adhesion bond parts, thereby diminishing joints.