S.F Tebyani - Department of Mining and Metallurgical engineering, Amirkabir University of Technology (Tehran Polytechnic),Tehran, Iran
K Dehghani - Department of Mining and Metallurgical engineering, Amirkabir University of Technology (Tehran Polytechnic),Tehran, Iran
M.H Hasanniya - Department of Mining and Metallurgical engineering, Amirkabir University of Technology (Tehran Polytechnic),Tehran, Iran

In this work, friction stir spot welding (FSSW) was applied to interstitial free (IF) steel sheets. The siliconcarbide (SiC) nanopowders with average diameter of 25 nm were then added to the joints in order to enhance themechanical properties and also to prevent the grain growth in the stir zone (SZ). The impact of welding parameters liketool rotating speed (1250 and 1600 rpm) and holding time (4 and 8 S) on the welds quality, were also investigated.Scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and tensile shear analyses revealed thatadding the SiC nanopowders to the welds led to noteworthy decrease in the grain size of SZ, remarkable increase in themechanical properties and hardness of the produced welds.

Interstitial free steel; Silicon carbide nano-particles; Friction stir spot welding