The Tensile Strength Comparison of 6xxx and 7xxx Series Aluminum Sheet Weldment using Laser Beam Welding and Friction Stir Welding Process

Abstract

Due to the high thermal diffusivity and metallurgical sensitivity, the proper welding processes of the aluminum are required. The Laser beam welding and friction stir welding processes have been focused as the appropriated welding processes for aluminum. The heat treated 6xxx series and 7xxx series aluminum sheet were welded by the laser beam welding and friction stir welding processes. Also, the effects of heat input through the welding parameters were investigated. The tensile strength of weldments was evaluated respectively and compared by the processes and heat input level. The insignificant tensile strength differences were found for the 6xxx series by the welding processes. However, the friction stir welded 7xxx series weldments were shown 82~89% joint efficiency while laser beam welded weldment were shown 48~58%. Overall, the effect of heat input level was not revealed in this experiment range. The degradations in hardness of weldments tended to be in proportion to the joint efficiency loss.

A Weldment Characteristics on Laser Welding of 2XXX Aluminum Alloys

“…으며 [5][6][7][8][9][10] , 용접부의 응고 균열(solidification cracking), 스패터(spatter), 기공(porosity) 등의 이유로 용 접강도가 저하되는 단점이 존재하여 적용에 한계가 있 었다. 하지만, 균열의 발생 기준 적립 11) 및 스패터 형상 연구 12) , 기공을 최소화하는 용접 조건 연구 13) 등이 이 루어지며 점차 적용 가능한 용접법으로 발전하였다 14) .…”