Dissimilar Weld Joint Performance of Micro Friction Stir Spot Welding with Pin Less Shoulder

Abstract

Micro Friction Stir Spot Welding is Friction Welding used to joint thin plat less than 1 mm. Each specimen has advantages of properties such as Copper has electrical properties better than aluminium however aluminium has other advantages, these advantages of both could be used in a construction or product. The differences properties and thin of metal as problem of friction welding. This study discussed a tensile test and a fracture analysis of a dissimilar weld joint from a copper with an aluminium sheet welded by Micro Friction Stir Spot welding for 0.5 mm of thickness from both metals. Tensile test represented the mechanical properties and fracture condition show the joining and mixed of both metals. A Copper plate on top from an aluminium plate were forced and swiped with a shoulder without a pin which was revolving with speed and time constant. The rotation speed 3000 rpm and friction time 60 sec were constant. The welding forces were used 40 and 50 kgf and shoulder diameters were applied 4 mm, 6 mm and 8 mm. This study could be concluded than the welding force 50 kgf could resist the tensile load more than 487 N with the longest strain and the fracture condition torn on aluminium side however this weld joint was not release. Friction Stir Spot Welding could join copper and aluminium with thickness less than 0.6 mm, it called Micro Friction Stir Spot Welding. The shoulder diameter specimen 4 mm with welding force 40 kgf and 50 kgf was not strong enough although the fracture weld joint of both metals shown torn of aluminium side and adhere on a copper plate. Bonding in weld joint could be studied by microstructure analysis.