Effect of Welding Parameters on Dissimilar Friction Stir Spot Welded Al-5083/St-12 Alloy Sheets

The present study investigates the effect of rotational speed and dwell time on the strength of Al-5083/St-12 friction stir spot joints. The welds were made using a newly developed FSSW process in which the tool pin did not penetrate into the lower steel sheet. Rotational speeds of 900 and 1100 rpm were applied in association with the dwell times in the range of 5-15 s. Results showed that the strength was first improved and then declined with increasing the dwell time. Furthermore, stronger joints were achieved at 900 rpm compared to the rotational speed of 1100 rpm.