Journal of Adhesion, Vol.90, No.5-6, 384-400, 2014
Surface Patterning of Metal Substrates Through Low Power Laser Ablation for Enhanced Adhesive Bonding
The aim of the present work is to study the effect of laser-induced surface patterning on the strength of adhesive joints. Laser ablation was carried out on aluminum alloy (AA6082-T4) and stainless steel (AISI 304) substrates using a pulsed ytterbium fiber laser (LaserPoint YFL 20P). The morphological and elemental modifications induced by the laser ablation were analyzed by means of surface profilometry, scanning electron microscopy (SEM), and X-ray photoelectron spectroscopy (XPS). In addition, surface wettability was analyzed by means of the sessile drop technique. In order to assess the capability of laser ablation to improve mechanical interlocking, cross-sectional areas of the samples taken across the interfacial region were probed under an optical microscope. Finally, mechanical tests were carried out on single-lap shear joints and the fracture surfaces were observed using the SEM. The obtained results showed that low power laser ablation can increase the strength of adhesive joints.