Laser transmission welding of thermoplastic fasteners: Influence of temperature distribution in a scanning based process

Abstract

Concerning the given challenges joining fiber-reinforced-plastics (FRP) by classic fasteners (for example rivets) a new approach is made by using thermoplastic fasteners joined by laser transmission welding (LTW). To achieve high quality joints the temperature distribution during the laser welding process between fastener and surface is important to prevent polymer degradation and to guarantee a homogeneous melting bath.Therefore, the influences of different scanning strategies and parameters (scanning path, velocity and numbers of repetitions) using a fiber laser and a scanning optic are investigated to achieve a favorable temperature field. The results show that not only a homogeneous temperature distribution, but especially the scanning path is important to generate high quality joints for the application of thermoplastic fasteners.