High-speed deformation of a high-strength coated thin plate

Abstract

The punch with cone-shaped working part impact into aluminum alloy thin-walled structures is mathematical modelled applying thermo-mechanical coupling of the physical processes during their deformation. The nonlinear physical properties contain a nonlinear stress-strain rate dependence of temperature. To solve the contact problem the sliding boundary conditions (friction) on moving bodies introduced. Numerical simulation of impact process performed using the finite element method and the independent Lagrange-Euler approach for two variants of the thin-walled box structure. The solution of the dynamic viscous plastic contact problem allowed to determine and to design the stress-strain fields in the thin-walled box section. For comparison, the deformation process of the similar aluminum construction with an additional rib considered when the punch with the conical working part impact. Analysis of stress-strain state for two various types of structural geometries demonstrated that mounting the additional medial rib into its design let redistribute the stress fields and significantly reduce the plastic deformation area during the impact because of four fold increasing in its contact stiffness. Such modification of the structure rigidity may improve the strength properties of the entire composite security device applying changes only to its part.