Friction stir welding of thermoplastic composites

Abstract

Polymer matrix composites (PMCs) are replacing traditional metals and unfilled polymers due to their superior properties such as excellent strength/stiffness-to-weight ratio with enhanced toughness and low cost. Friction stir welding (FSW) is a new addition for joining of plastics and it has many advantages when compared with traditional joining process. The aim of this work is to investigate the feasibility of glass-filled Nylon 6 composites by FSW. Glass-filled Nylon 6 composites were fabricated by an injection molding machine and joined by FSW process with H13 tool steel with cylindrical pin profile. In order to study the mechanical and morphological properties of FSWed sections of glass filled Nylon 6composites, a full factorial design of experiment was employed using the factors like tool rotational speed (400, 500and 600 rpm), tool traverse speed (0.2, 0.3 and 0.4 mm/s) and tool tilt angle (0°, 1° and 2°) having constant standoffdistance 0.2 mm. Analysis of variance (ANOVA) was used to find out the significance of process parameters (tool rotational speed, tool traverse speed, and tool tilt angle) with the tensile strength, and percentage elongation. The optimized result was achieved at a tool rotational speed of 600 rpm, welding speed of 0.2 mm/s, and tilt angle of 2° with defect-free welds. It is observed that joining of glass-filled Nylon 6 composites is feasible one with proper selection of process parameters and tool rotational speed has a significant effect on weld strength followed by tool traverse speed and tool tilt angle.