Effect of coating thickness on electrode life in the spot welding of galvanized steels

This study examined the effect of coating thickness on electrode life and nugget strength. Uncoated and galvanized steel sheets supplied from Eregli Iron and Steel Factories Co. (Erdemir) with similar chemical compositions having different coating weights (100, 180, and 275 g/m2) were welded using resistance spot welding under constant welding parameters. Electrode force used during spot welding operation was 7.3 kN under 6.5 kA of constant welding current and 2 s welding time. After welding operations, shearing tests were applied to selected specimens and the nugget diameters were measured. Experimental results showed that as the coating thickness increased the electrode life and the strength of the weld nugget decreased. © TÜBİTAK