MECHANICAL AND OPTICAL INVESTIGATION OF LASER WELDED STRUCTURAL STEEL - POLY(METHYL-METHACRYLATE) HYBRID JOINT STRUCTURES

Abstract

Modern welding processes that can easily be automated (such as friction stir welding, laser welding and ultrasonic welding) are gaining popularity in joining metal-polymer hybrid structures. This field of science is intensively studied around the globe, as a dependable, productive joining method that directly produces structurally sound joints between a metal and a polymer structure could unleash unforeseen possibilities in the vehicle industry. In our experiments, we manufactured hybrid steel-poly(methyl-methacrylate) (PMMA) joints with laser welding, using the 2p design of experiment method. We measured the effect of cellulose reinforcing fibres (in varying weight percentages) on the transparency and weldability of the PMMA material and the effect of welding parameters on the mechanical properties of the joints. We also examined the vicinity of the welded seam with scanning electron microscopy.