Investigation of ultrasonic welding of CF/PA66 using stainless steel mesh energy directors

Abstract

This paper employs stainless steel mesh as energy director (ED) to join carbon fiber reinforced PA66 composite (CF/PA66). The effect of mesh size on the lap-shear failure load, cross-sectional microstructure, and fracture morphology is investigated. The results show that the mesh size has important impact on the weld formation and joint mechanical property. A small wire spacing leads to more pore defects in a joint; a large wire diameter increases the lack of fusion defects, and a large mesh area reduces the energy concentration effect. Mesh energy directors with large wire spacing, small wire diameter, and small area contribute to high joint strength. Under the appropriate welding energy and mesh size, the failure loads of joints are above 10000 N, and the failure model of these joints is workpiece fracture.