Experimental and Numerical Studies on the Forming Behavior of Interstitial-Free Steel Sheet

It is a comprehensive study of forming behavior of interstitial-free steel sheet following the Erichsen cupping test in order to find out the ductility of the metal sheet. The Erichsen cupping test measures forming behavior by subjecting the metal sheet to a gradually increasing force until it deforms and forms a cup-shaped depression. Three sheets of 0.7, 1.2, and 1.5 mm thickness has been used for the test. Tensile test gives us the value of yield strength and ultimate tensile strength along with strain-hardening exponent and strength coefficient. Anisotropy is calculated in 0°, 45° and 90° rolling direction. Vickers micro-hardness test is done in order to find out the hardness of the IF steel. Finite element analysis is done by applying appropriate material model and boundary conditions for accurate prediction of sheet formability and cupping behavior. Important aspects like strain distribution and stress concentration are studied. The results that are obtained after the simulation are then validated against the experimental value and on comparing the experimental and simulated value matches quite well with depth of cup.