Influence of laser texturing strategy on thermomechanical joining of AA7075 aluminum alloy and PEEK

Abstract

The present investigation aimed to determine the influence of the texturing strategy on the mechanical behavior of metal-polymer hybrid joints made by friction-assisted joining. An experimental campaign was conducted on AA7075 aluminum alloy and PolyEther Ether Ketone (PEEK). Laser texturing was performed on the aluminum surface before joining to improve the mechanical interlock between the substrates. Different laser texturing conditions were used by varying the number of scans and the distance between consecutive laser tracks. Microscopic analysis was conducted on the treated samples to determine the main geometrical characteristics. Single-lap shear tests were performed to determine the mechanical behavior of the produced connections. Fracture surface analysis was also performed to establish the main failure mechanisms. According to the achieved results, the laser texturing strategy significantly influenced the mechanical behavior of the joints, the peak force, the absorbed energy, and the failure mode. The density of the laser texturing affected the stress on the aluminum protrusions and the mechanical behavior. Adopting a higher number of scans improved the mechanical interlock and, consequently, the mechanical behavior of the joints.