Fatigue Life of Friction Stir Welded Polyphenylene Sulfide

High performance polymeric materials have excellent mechanical properties. So the process of joining requires a similar type of bonding in terms of durability and strength to the original material itself. In this research, the Friction stir welding method was chosen to joining polyphenelyne sulfide. Friction stir welding, a solid state joining process is an already demonstrated procedure for the welding of metals. Of late, it has been utilized on polymers, which additionally have indicated effective joining results. Several factors have been tested and studied for their effect on weld quality. First,two types of pin diameters were compared 3 mm and 6 mm and then three types of rotational speed were changed to (1,250, 1000, 800) rpm with transvers speed 30 mm/min, then a transvers speed 60 mm/min was selected and compared with transvers speed of 30 mm/min results. Finally, Shoe tool was used as a means to prevent the release of molten polymer outside the welding boundary under conditions of 1250 rpm and 60 mm/min.Mechanical properties including fatigue tests of all the welded samples were investigated. Microstructural analysis using optical microscope and SEM.The result was that the pin of 6 mm diameter gave higher fatigue life from pin with 3mm dimeter, and the 1250 rpm speed was the best in terms of fatigue life among the other values of speeds, The result was that the pin of 6 mm diameter gave higher fatigue life from pin with 3mm dimeter, and the 1250 rpm speed was the best in terms of fatigue life among the other values of speeds, So the 60 mm/min transvers speed was the best in two rotational speeds (1000 and 1250) rpm. But the ideal case was by using the shoe tool, where the 75% of the fatigue life was obtained.