Solid State Friction Stir Welding (FSW) on Similar and Dissimilar Metals

Welding is a process which helps to join metals by adding metals between weldments by diffusion process.. One of the process by which metals are joined by creating friction on metals. It is called solid state welding. A rotating hard cylindrical pin is pressed on metals to be welded by friction. In FSW, there are only three process variables to control: rotation speed, travel speed and pressure, all of which are easily controllable. Four rotational speeds were used keeping the feed rate constant. The plunge depth is related directly to the pressure was varied depend on the work material. Analysis was carried by measuring surface roughness (RA), tensile, micro hardness and metallographic tests. At rotational speed of 1925 RPM, aluminum to aluminum welding had given ultimate tensile strength up to 86 percent. Copper to copper joint process resulted that at rotational speed of 2275 RPM is the best result. Tensile value of 74 % was obtained compared to copper base material. The surface roughness Ra value low compared to copper base metal. The Vickers hardness value was high compared to base metal. Aluminum to copper metal joint the best resulted at 2275 RPM. The result was the lowest compared to similar metal joints. The value of 427 MPa of ultimate tensile strength (UTS) was archived. The metallographic test showed that a crack occurred at the bottom of welding joint. The hardness test showed that the hardness at the joint increased drastically. At high rotational speed of 2975, low surface roughness was obtained in all the weldments at low feed rate and low plunge depth.