Welding Properties of Polymeric Nanocomposite Parts Containing Alumina Nanoparticles in Friction Stir Welding Proces

Although in recent years, welding of polymers has been developed but welding of polycarbonates is still faced with serious challenges such as improving the quality of welded section. In the present study, mechanical properties of polycarbonate friction stir welded samples with different nano alumina content were investigated. For this purpose, firstly polycarbonate (as matrix) was melt compounded with nano alumina in variant weight percentages including 0, 1, 2 and 3% using a twin-screw extruder. Then, nanocomposite samples were produced using an injection molding machine and were friction stir welded with a special tool on a milling machine. The effects of weight percentage of nano alumina, travel and rotational speeds (all in four levels) were investigated on the tensile strength and hardness of the welded nanocomposite samples according to a L16 orthogonal array of Taguchi method. According to the obtained results, the weight percentage of nano alumina is the most effective parameter on the tensile strength and hardness of welded nanocomposite specimens. By increasing the percentage of nano alumina to 1%, tensile strength increased. However, by increasing the nano alumina more than 1%, this strength reduced due to agglomeration of nanoalumina in high weight percentages. Results also demonstrated that processing parameters do not affect the mechanical properties of welded nanocomposite samples significantly.