Experimental studies on strength of friction stir spot welding (FSSW)

Friction Stir Spot Welding (FSSW) is a derivative of the friction stir welding (FSW),
novel variant of the "linear" FSW process. It creates a spot, lap-weld without bulk
melting with vertical movement of a non-consumable tool during the welding operation
on overlapping sheet metal with small range ofthickness for soft metal like aluminium. It
has been used in the production of aluminum doors, engine hoods, and deck lids in the
Japanese automotive industry, aerospace, transportation, and automotive industry
globally [2l It has the benefits ofoperation and investment cost savings, weight reduction,
high repeatability and consistence, low maintenance, better work environment,
environmental metal joining and recyclability versus other aluminum spot joining method
t2l This dissertation Final Year Project onFriction Stir Spot Welding (FSSW) reports the
experimental study on strength of overlapping Aluminum 1100 sheet metal which applies
the welding method. CNC Mazak Integrex 200-III is used to fabricated tool steel while
CNC Mazak Variaxis 530 5-X is used for implementing the welding technique. Pull to
break test is used to obtain maximum load (N) before break for the overlapping sheet
correspond to lap-shear force. Overall result obtained shows that the lap-shear strength of
overlapping sheet decreases by increasing or decreasing tool rotational speed and
penetration rate beyond the optimum combination.