Influence of energy induced from processing parameters on the mechanical properties of friction stir.pdf

ORIGINAL ARTICLE Influence of energy induced from processing parameters on the mechanical properties of friction stir welded lap joint of aluminum to coated steel sheet Hrishikesh Das Sushovan Basak Goutam Das Tapan Kumar Pal Received: 13 October 2011 /Accepted: 2 April 2012 # Springer-Verlag London Limited 2012 Abstract Friction stir welding has been attempted to evaluate joint strength of lap joint between aluminum sheet (AA6063) and zinc-coated steel (HIF-GA) sheet under different combina- tion of rotational speed and traverse speed. The shear strength decreases significantly when rotational speed increases from 700 to 1,500 rpm at a traverse speed of 30 mm/min. At traverse speed of 50 mm/min, increasing rotational speed from 700 to 1,500 rpm, shear strength remains more or less the same. However, at a traverse speed of 100mm/min, the shear strength increases significantly with increasing rotational speed from 700 to 1,500 rpm. Essentially, higher fracture load of the lap joint is obtained within a certain range of energy. The results have been correlated with the microstructural characteristics at the bond interface using energy dispersive X-ray spectroscopy, electron probe micro analyzer, and X-ray diffraction. The results show that characteristics of intermetallic compound formed at the interface derived from energy input takes pre- dominating role towards lap joint of Al and coated steel. Furthermore, force and torque responses influenced by the processing parameters can be utilized as weld quality check. Keywords Friction stir lap welding (FSLW) . High strength interstitial free steel (HIF) . FSW parameters . Intermetallic compound (IMC) . Force . Torque 1 Introduction In the automotive industry, demand for greater fuel economy has created a continuous need for lighter weight vehicles. Historically, the majority of automobile structure components have been made of steel. The use of zinc-coated steels for the automotive body construction has increased sign