Friction Press Joining of Laser-Texturized Aluminum with Fiber Reinforced Thermoplastics

Abstract

Friction Press Joining (FPJ) is a suitable method for producing composites of aluminum and thermoplastics in lap joint configuration, which is based on modified Friction Stir Welding (FSW). During the joining process, a rotating cylindrical tool is pressed onto an aluminum surface. The resulting friction generates heat that is conducted to the bonding zone, leading to localized softening of the thermoplastics. In combination with the tool’s axial force and a suitable pre-treatment of the aluminum surface, a resilient composite compound is created. This paper presents the results of a surface pre-treatment of aluminum using laserradiation. The textures are essential for a strong connection, as they can significantly influence effective joining mechanisms, such as microscopic and macroscopic form fit. The experiments were carried out using different surface treatments by means of a single-mode laser for joints of aluminum (EN AW-6082 T6) and glass fiber reinforced polyamide (PA6 GF15). The aim of the study was an increased understanding of process behavior and joining mechanisms. The shear strength could be increased by 40 % compared to previous studies with the presented laser surface treatment.