Forming limit diagram for Indian interstitial free steels

In this work, the suitability of interstitial free steel sheets of thickness 0.6 and 1.6 mm for press forming operations were examined by obtaining the forming limit diagram. The microstructural aspects, tensile properties and formability parameters were studied. Forming limit diagrams (FLD) were evaluated for the above sheet metals of two different thicknesses and they were compared. Strain distribution profiles were obtained from the forming experiment. The fracture surfaces of the formed samples were observed using scanning electron microscope. Using the fractography, the fracture behaviour and formability were analyzed. The tensile properties and formability parameters were correlated with the FLD. It was found that the formability of both sheets is good and the sheet with 1.6 mm thickness was superior.