Finite element analysis of the response of DP800 steel sheet in a new laboratory forming test

Abstract

Owing to the good formability combined with low yield-to-ultimate tensile strength ratio, DP800 steel is widely used in the automotive industry. For process optimization and analysis of the feasibility and resulting part quality, it is essential to use a suitable constitutive model. To assess the predictive capabilities of models for forming applications, very recently a benchmark focusing on simulation of a new laboratory forming test, called material under control (MUC) was launched. In this paper, we show that an elastoplastic model with yielding described by the 3-D orthotropic yield criteria of Hill48 [1] and Cazacu [2], and isotropic hardening accurately predict the observed plastic anisotropy of the DP800 steel. The predictive capabilities of these models are demonstrated through comparisons between simulation results and experimental data in uniaxial tension and MUC-Tests, including punch force-displacement curves and surface strain distributions for all specimen geometries. Furthermore, the effect of specimen orientation on the strain path experienced by the material during a MUC test was investigated using Cazacu [2] criterion. The results presented suggest that the use of 3-D orthotropic yield criteria and isotropic hardening may provide reliable virtual assessments of DP800 steel for forming operations.