Abstract
In this study, the effects of weld current and weld time on the tensile peel strength and tensile-shear strength of 7114 grade IF (Interstitial–Free) steel sheets joined by spot welding were investigated. Weld processes were performed by using 3-5-7-9 kA weld current and 5-10-15-20-25-30 weld cycles. The microstructure of the welded materials was evaluated. The hardness profiles were also determined. Experimental results showed that tensile shear loading bearing capacity and hardness of both weld and heat affected zones increased for increasing weld time and weld current. Weld nugget diameter extended by increasing weld time or/and weld current, so tensile shear load bearing capacity and tensile peel strength increased. Tensile fracture behaviour of the samples was evaluated. Weld lobe was constructed with respect to weld current and time.

Key words
Interstitial free (IF) steels, welding, mechanical properties

Full text (350 KB)