Repair of automotive bumpers and bars with modified friction stir welding

Abstract

This study reports the investigations for repair of thermoplastic based automotive bumpers and bars with modified friction stir welding (MFSW) process. For MFSW, consumable tool of polyamide6 (PA6) composite has been used for joining of acrylonitrile butadiene styrene (ABS) composites. The dissimilar thermoplastics were processed for maintaining a useful range of melt flow properties followed by preparation of feed stock filament for fused deposition modeling (FDM) process through screw extrusion. Finally, 3D printed PA6 based consumable rapid tool (RT) was prepared for MFSW. The joints prepared were subjected to flexural, hardness, morphological and thermal testing. The study has suggested the that maximum mechanical strength was obtained for sample welded at 1400 r/min, 50 mm/min transverse speed and 3 mm plunge depth, whereas the minimum mechanical strength was obtained for sample welded at 1000 r/min, 30 mm/min transverse speed and 2 mm plunge depth. The results are also supported with thermal analysis and photomicrographs.