The effect of tool geometry on the tensile strength of polypropylene Components Welded by Friction Stir Welding Method

Friction stir welding is one of the new methods of solid state welding. This welding method has many advantages over traditional methods of fusion welding due to low input temperature and non-melting and freezing of materials. In this study, the tensile strength variations of the welded specimens were investigated based on two parameters of the geometry of the tool and the angle of the device for the welding of polypropylene sheets. In order to obtain the optimal value of these parameters, other variables such as rotational speed and linear velocity of tools are assumed constant. After welding the samples, a standard tensile test was performed on the samples. The results show that the tool geometry has a great influence on the tensile strength and the appearance of the weld and the pieces welded by the tools with a welder's helmet have a higher strength. Also under the same conditions, the highest tensile strength is when the angle of the machine is 2°.