Effect of welding speed on microstructure and mechanical properties of friction-stir-welded aluminum

The weld properties remain an area of uncertainty with respect to the effect of different speeds of friction stir welding (FSW). For this purpose, hardened steel tool of FSW was used, which consists of the shoulder and pin. The shoulder of the tool not only provides additional heat generated by friction but also prevents plasticized material to escape. In the present investigation, aluminum welds were made at various welding speed using the FSW technique. The welds were characterized for mechanical properties and microstructural investigation. It is observed that good correlation exists between the mechanical properties and welding speeds. The best mechanical properties were obtained at lower welding speed.