Identification strategy of anisotropic behavior laws: application to thin sheets of Aluminium A5

Abstract

Numerical simulation provides a valuable assistance in the controlling of forming processes. The elasto-plastic orthotropic constitutive law is based on the choice of an equivalent stress, a hardening law and a plastic potential. An identification of the model parameters from an experimental database is developed. This database consists in hardening curves and Lankford coefficients of specimens subjected to off-axis tensile tests. The proposed identification strategy is applied to aluminum sheets. The behavior of this material is studied under several solicitations. The anisotropic behavior of the aluminum plate is modeled using the Barlat criterionand the hardening law. The obtained Lankford coefficients are compared to those which are identified by a different strategy.

Experimental and numerical study on mechanical properties of aluminum alloy under uniaxial tensile test

“…3 indicate that the 7075 in temper T7 is defined by maximum percentage elongation along the rolling direction and minimum value along the transverse direction. The 7075-T7 aluminum alloy has high mechanical properties both in terms of strength and ductility compared to pure aluminum A5 [16]. Maximum yield R e and tensile R m strengths are observed especially in the transverse direction but a significant decrease in percentage elongation A%.…”

Identification of the anisotropic behavior of an aluminum alloy subjected to simple and cyclic shear tests

“…It is worth noting that the commonly used uniaxial tensile test is not sufficient due to premature failure especially in the case of very thin sheets as already observed on aluminum alloys. 22,33,34…”

“…It is worth noting that the commonly used uniaxial tensile test is not sufficient due to premature failure especially in the case of very thin sheets as already observed on aluminum alloys. 22,33,34 Initially, simple shear tests at room temperature were carried out in three loading directions 0 , 45 , and 90 with respect to the rolling direction. Figure 11 shows the hardening curves in three loading directions 0 , 45 , and 90 .…”

“…It describes satisfactorily the behavior of pure aluminum in simple tensile. 33 σs(εp) is the isotropic hardening function where εp is the plastic strain.…”

“…A brief description of their equations and the acronyms that will be used for these models in the presentation of the numerical results are given. Three classical isotropic hardening laws are selected from literature 22,33,34 to describe the plastic behavior of aluminum and its alloys.…”