OPTIMIZATION OF FSW PROCESS ON UHMWPE BY USING HEXAGONAL TOOL PROFILE

Friction stir welding (FSW) is a solid-state joining process that uses a non-consumable tool to join two facing workpieces without melting the workpiece material. Heat is generated by friction between the rotating tool and the workpiece material which leads to a softened region near the FSW tool. While the tool is traversed along the joint line it mechanically intermixes the two pieces of metal and forges the hot and softened metal by the mechanical pressure which is applied by the tool much like joining clay or dough. It is primarily used on wrought or extruded aluminium and particularly for structures which need very high weld strength. FSW is capable of joining aluminium alloys copper alloys titanium alloys mild steel stainless steel and magnesium alloys. More recently it was successfully used in welding of polymers. In addition joining of dissimilar metals such as aluminium to magnesium alloys has been recently achieved by FSW. Application of FSW can be found in modern shipbuilding trains and aerospace applications.