부산대학교 도서관

In this study, the mechanical properties of friction stir welded A6061-T6 were evaluated. This material is used as a battery pack case material for electric vehicles. The Vickers hardness, tensile strength, and yield stress of the friction stir welding (FSW) specimen were all smaller than those of the base metal specimen. As the heat input increased, the nugget zone widened, and there were differences in hardness according to the base metal zone, heat affected zone, thermal-mechanical affected zone, and nugget zone. Mechanical properties were not proportional to heat input, and the thermal-mechanical affected zone on the advancing side was the smallest in all conditions. This is because the material flow speed increased on the advancing side, where the welding direction and the tool rotation direction were the same, forming a distinct boundary with mechanical deformation.