Short cylindrical specimens made of AA6082-T6 aluminum alloy were studied experimentally (compression tests), analytically (normalized Cockcroft-Latham criteria—nCL), and numerically (finite element analysis—FEA). The mechanical properties were determined with the stress-strain curves by the Hollomon equation. The elastic modulus obtained experimentally differs from the real value, as expected, and it is also explained. Finite element (FE) analysis was carried out with satisfactory correlation to the experimental results, as it differs about 1,5% from the damage analysis by the nCL concerning the experimental data obtained by compression tests. 1. Introduction Mechanical properties of ductile materials are normally determined by tensile test. However, when the plastic deformation is the aim of the study, the compression test is the most suitable as it allows large deformations without the fracture of the specimen. For this test, the cylindrical specimen is the most adopted. However, in this case, the damage must be evaluated. Numerical analysis (i.e., finite element analysis—FEA) may be used to predict the damage for materials with elastic-plastic behavior. But, first, it is needed to perform classical model (analytical) and material (experimental) analysis. Many studies were carried out concerning aluminum under axial compression; among them, Hopperstad et al. [1], Andrews et al. [2], and Gioux et al. [3] studied the compression of aluminum foams. Ferguson et al. [4] proposed an analytical model for predicting the mechanical properties of bimodal nanoaluminum alloys, concerning the grain size. Pled et al. [5] have done a numerical study of the crushing of circular aluminum tubes, with and without aluminum foam fillers. Han and Kim [6] proposed a new criterion for ductile fracture in sheet metal forming process. Luo et al. [7] performed isothermal compression tests of 7A09 aluminum alloy concerning solid cylindrical specimens. Rees [8] studied aluminum alloy sheets by plane strain compression. Wu et al. [9] determined the flow behavior and constitutive equations of 7050 aluminum alloy in isothermal compression. Kyakaj et al. [10] studied the workability of AlMgSi aluminum alloy prepared by powder metallurgy, by means of analytical (damage) and numerical methods. Some researches concerning damage of other metals have also been done, and some are listed here: Stefanik et al. [11] have determined the values of the normalized Cockcroft-Latham (nCL) for multi slight rolling based on tensile test of BSt500S steel. Xia et al. [12] studied the effects of
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