Effects of Rotational Speed on Joint Characteristics of Green Joining Technique of Dissimilar Polymeric Rods Fabricated by Additive Manufacturing Technology

Friction welding (FW) FW of dissimilar polymer rods is capable of manufacturing green products swiftly and economically. In this study, a green manufacturing technique of joining dissimilar polymer rods was proposed, and the effects of rotational speed on the joint characteristics of friction-welded dissimilar polymer rods fabricated by the fused deposition modeling process were investigated experimentally. The shore surface hardness test, impact test, three-point bending test, and differential scanning calorimetry analysis were carried out on the weld joints. The impact energy for FW of polylactic acid (PLA) and PLA, PLA and acrylonitrile butadiene styrene (ABS), PLA and PLA filled with glass fiber (GF), PLA and PLA filled with carbon fiber (CF), PLA and polycarbonate (PC), and PLA and polyamide (PA) rods can be increased by approximately 1.5, 1.5, 1.3, 1.3, 2.1, and 1.5 times by increasing the rotational speed from 330 rpm to 1350 rpm. The bending strength for FW of PLA and PLA, PLA and ABS, PLA and PLA filled with GF, PLA and PLA filled with CF, PLA and PC, and PLA and PA rods can be increased by approximately 1.3, 1.7, 1.3, 1.2, 1.2, and 1.2 times by increasing the rotational speed from 330 rpm to 1350 rpm. However, the surface hardness of the weld bead is not proportional to the rotational speed. The average surface hardness of the weld bead was increased by approximately 5% compared to the surface hardness of the welding base materials.