Investigation of the effect of friction force on the energy absorption characteristics of thin-walled structures loaded with axial impact force

Abstract

In recent years, there has been a significant increase in studies aimed at enhancing the energy absorption capabilities of thin-walled structures used in vehicles. These studies aim to mitigate the adverse effects of shock waves released during crashes by incorporating recesses that trigger folding on the walls of crash boxes, thereby increasing energy absorption. This particular study investigates the energy absorption and crushing behaviors of interpenetrating thin-walled structures under axial crushing conditions. Two different configurations were modeled to determine the contribution of friction force in dampening impacts in thin-walled structures. One configuration exhibited classical folding, while the other initiated folding after interpenetration upon the application of an axial impact load. The interpenetrating structures generate friction forces through recesses and protrusions on the surface of the crash box to provide energy absorption. The simulations were conducted using the finite element method (FEM) in a non-linear explicit dynamic collision scenario. The crash scenarios for both configurations were analyzed under identical conditions using two different materials (DP-600 and DP-800) and three different thicknesses (1.2 mm, 1.4 mm, and 1.5 mm). The dynamic crash simulations were compared based on Specific Energy Absorption (SEA), Total Energy (ET), Peak Crush Force (PK), Crush Force Efficiency (CE), and Mean Crushing Force (FM) values to examine the effects of friction force on energy absorption capabilities and crushing behaviors of the crash boxes. The analysis results demonstrated that friction force and energy absorption play a positive role in the crashworthiness characteristics of thin-walled structures. © 2023 Elsevier Ltd