Abstract:
A joining of two different materials was widely applied in various industries such as an automobile industry, electrical industry and electronic industry. The advantages of this joint are increasing flexibility of the joint and decreasing the gross weight of the structure. It is also affecting the energy saving of the automobiles. This research aims to study the effects of friction stir spot welding parameters upon the tensile shear strength and the microstructure of the lap joint between AA5052 aluminum alloy and C11000 copper alloy.
The research was carried out by using a friction stir spot welding of the lap joint between AA5052 aluminum alloy and C11000 copper alloy. The experiments were conducted by varying important welding parameters such as rotating speed, pin insert rate and holding time. The joints that produced by given welding parameters were tested for their mechanical properties and examined their microstructure of the joints.
The experimental results showed that the maximum tensile shear strength of 864 N could be obtained by applying welding parameters at rotating speed of 3,500 rpm, the pin insert rate of 6 mm/min, and the holding time of 4 s. It was also founded that the increasing the rotating speed and the pin insert rate will resulted in increasing the tensile shear strength. The increasing of the shear strength was due to the high hook at the joint interface beneath the tool shoulder that can be observed by the examined macrostructure. Moreover, the examination of the microstructure at the joint interface showed the area that copper and aluminum were mixed. This also resulted in increasing the tensile shear strength of the lap joint.