Yield criterion influence on the formability prediction of SS 304 by tensile tests and bulge tests during tube hydroforming process

Finite element (FE) simulation of sheet/tube forming precision depends mainly on the accuracy of the yield surface shape used in mechanical modeling. The yield surface mainly depends on the number of input variables used to define the yield surface. The present paper's aim is to compare the constitutive models to fit the hardening laws. The accurate deformation behavior of the SS 304 tubes depends on the constitutive modeling of hardening behavior. Deformation data of the tubular samples were collected by conducting uniaxial tensile tests and tube bulge test. The best fitted constitutive hardening model was utilized on both Hills 1948 and Hills 1990 yield criteria and the accuracy of the simulations was predicted. Thickness and strain distributions, as well as the geometry of the bulged specimen, were taken as comparison parameters. Experimental validation was performed on all the available predicted data and was observed to be best for the Hills 1990 yield criteria.