No abstract

This research paper aims at studying the friction stir spot welding (FSSW) some of thermoplastic polymer materials (HDPE and HDPE-PMMA) using a specifal geometry tool without a pin. The effect of the tool geometry on the welds static resistance was studied via several tool shape, a flat shape below the tool, a shape with concavity angles ranging from 0° to 16° , a flange shape of the sharp-edged tool, a chamfered flange shape and a rounded shape. This work is done to increase the surface area of the weld and further to maximize the static strength of the friction stir spot welding. Experimental tests have been carried out under various operational parameters such as the tool rotation speed, tool plunge depth and dwell time. This later has been carried out to highlight the effect of the tool’s geometry and the operational parameters of the welding on the surface in virtue on static resistance of the friction stir spot welding of thermoplastic polymers. Tests of lap-shear at speed of 5m/s have showed that the tool geometry plays a very important part. This study shows that a FSSW welding tool with 4° concavity angle tool and a rounded flange shape gives the best welding quality for the polymers studied.