Forming limit diagram for interstitial free steels Part I

The suitability of interstitial free (IF) steels of thickness 0.9 and 1.2 mm for press forming operations were examined. The microstructural aspects, tensile properties and formability parameters were studied. Forming limit diagrams were evaluated for the above sheet metals and they were compared. Strain distribution profiles were obtained from the forming experiment. The fracture surfaces of the formed samples were viewed using scanning electron microscope (SEM). Using the fractography, the fracture behaviour and formability were analyzed. The tensile properties and formability parameters were correlated with the FLD. From the analysis, it was found that IF steel having 1.2 mm thickness is superior compared to the other one.