Tensile shear strength and dynamic mechanical analysis of 6063 aluminium alloy and 304 stainless steel sheet by spot welding

Abstract

Mechanical properties of dissimilar metal of spot welding were tested and analyzed with different parameters which were welding current and welding time. From visual observation, the largest weld nugget recorded was 7.43 mm at 5 kA, while the smallest was 6.4 mm at 3 kA. It found that weld nugget size increase with the increment of weld current and extension of weld time. In tensile properties, the largest weld nugget size of 7.43 mm have the highest tensile strength, 31.99 N/mm2 , while the smallest weld nugget 6.4 mm have 29.40 N/mm2. Findings show that weld nugget size affect the tensile shear strength, and with the increment of weld current and extension of welding time, tensile shear strength increase. Dynamic mechanical properties defined the storage modulus, loss modulus and damping capacity of dissimilar metal spot welded. It found that at 10 Hz between 70°C to 350°C, with heating rate of 10°C/minute, the storage modulus increase with increment weld current and the extension of weld time. While the loss modulus decrease with the increases of weld current and weld time. Same pattern happen to damping capacity, the value dropped with the increases of welding current and welding time.