A comparison of different hardening rules on a multi-step global manufacturing process modeling

Abstract

The main difficulty presented by the simulation of a global process that includes different forming stages is the correct characterization of the material state at the end of each of these stages, which in turn, are the initial point of the following process. Hardening variables are capable of characterizing the state of the material, which, after a plastic transformation, varies according to the direction of the solicitation and its intensity. The present work carries out an analysis of the influence in the election of the hardening rule used in the behavior law, comparing the most used approach. For a work piece solicited by combined efforts in multiple stages, results are obtained by numerical simulation. A correct choice will allow obtaining reliable predictions, not the solicitations but also to the final geometry and the dissipated energy in the global process, allowing an eventual optimization of such process.

A Review of Sheet Metal Forming Evaluation of Advanced High-Strength Steels (AHSS)

“…The hardening laws play a crucial role in describing how the yield surface evolves under plastic deformation and various loading conditions. These laws can be categorized into four main families [156]: (i) isotropic, (ii) kinematic, (iii) anisotropic; for example, distortional hardening, and (iv) combined. Isotropic hardening implies that the yield surface expands without changing its shape as plastic strain increases.…”