Effect of ultrasonic amplitude and riveting speed on mechanical properties of Ti-45Nb riveted lap joints

Ultrasonic vibration-assisted machining has been introduced as a new process in riveting aircraft components. In this paper, the effects of different ultrasonic amplitudes and riveting speeds on the quality, shear properties, and cross-tension properties of riveted joints are investigated. The failure sample fracture was characterized using a scanning electron microscope and the cause of the fracture was discussed. The results show that the ultrasonic amplitude is negatively correlated with the height of the riveted joint and positively correlated with the diameter of the riveted joint. The maximum shear failure load was obtained at a riveting speed of 5 mm/s with an ultrasonic amplitude of 35.3 mu m, and the maximum cross tensile failure load was obtained at an ultrasonic amplitude of 23.3 mu m. All shear fractures occurred in the rivet shanks and all cross fractures occurred in the rivet manufactured head, and the failure modes of both shear and cross-tension fracture were mixed brittle and plastic fracture modes.