Steel Sheet Forming Isotropic Or Anisotropic

Ive worked with ls dyna before.

Steel sheet forming isotropic or anisotropic.

Anisotropy includes elastic and plastic anisotropy. A bifurcation analysis of forming limits for an orthotropic sheet metal is presented in this paper. Specifically a special attention is paid to the physically based hardening model of teodosiu and hu 1995 which accounts for the anisotropic work hardening induced by the microstructural evolution at large strains as well as to some more conventional hardening models. For most sheet materials under these complex loading processes used in industry strong bauschinger effect is observed and the material hardening behavior tends to be anisotropic.

The ferritic stainless steel shows strong anisotropic plastic deformation in terms of both yielding and hardening whereas the dual phase steel behaves quite isotropic resulting from the mixture of two phases. There it was possible to define the material with the barlat 91 six component yield function. In anisotropic yield functions sheet metals are assumed to be orthotropic whereby the rolling direction rd or 0 the transverse direction td or 45 and the normal direction nd form the symmetry axes. This microstructure generates a directional dependency of the plastic properties which is called anisotropy.

For that reason anisotropic yield functions are often utilized such as hill barlat or bbc. Im trying to define an anisotropic material in abaqus. In cold rolled sheets elastic deformation is much smaller compared with the plastic deformation so only the anisotropic plasticity is nor mally considered. Plast 26 9 2010 pp.

Laser forming process however have not been studied in detail while most sheet metal materials used in the laser forming are cold rolled. Isotropic yield functions cannot reflect this directional behavior. The variation of their plastic behavior with direction is assessed by a quantity called lankford parameter or anisotropy coefficient 4 1. Zhaospringback investigation of anisotropic aluminum alloy sheet with a mixed hardening rule and barlat yield criteria in sheet metal forming mater des 31 4 2010 pp.

Vladimirov i n pietryga m p reese s anisotropic finite elastoplasticity with nonlinear kinematic and isotropic hardening and application to sheet metal forming int.