Analysis of metallic materials behavior during severe loadings using a FE modeling of the SHPB test based on a numerical calibration of elastic strains with respect to the raw measurements and on the inverse analysis principle

摘要

The complex loading paths of non-conventional or rapid forming processes, especially as regards the important gradients of the plastic strain and strain rate characterizing the material deformation, require a reliable knowledge of the rheological constitutive equations. Consequently this paper proposes to improve the experimental data accuracy obtained from high speed mechanical tests using the Split Hopkinson Pressure Bar (SHPB) device. Finite element simulations of the entire experiment are proposed, together with some applications concerning the use of different specimen shapes to obtain a large range of plastic strains and strain rate values. A description of the inverse analysis strategy, applied in order to analyze the thermo-mechanical constitutive behavior of metallic materials and the identification of the corresponding rheological parameters, is presented.