Energy Absorption Characteristics of Crash Box of New Honeycomb Core Structure with Foam-Filled

Abstract

By combining honeycomb core with the traditional crash box, an innovative foam-filled honeycomb core structure crash box is proposed to improve safety performances. Three kinds of honeycomb core crash boxes were obtained by filling the inside of the traditional crash box with the quasi-honeycomb core, the quasi-square honeycomb core and hexagonal honeycomb core. It is deduced that the energy absorption of the quasi-honeycomb core crash box increased by 42.2 %, the peak of the collision force reduced by 8.9 %. The hexagonal honeycomb core crash box and the quasi-square honeycomb core crash box also enhance the energy absorption characteristics, but the peak impact force increased by 5.6 % and 9.6 %. After filling of the Expanded Polypropylene (EPP) foam, the peak collision force of the EPP hexagonal honeycomb core crash box and the EPP quasi-square honeycomb core crash box increased by 10 %, while Fmax of the EPP quasi-honeycomb core crash box reduced by 2.3 % and the energy absorption increased by 54.6 %. Six structures were compared to highlight the energy absorption characteristics of the filling the inside of the traditional crash box with the light in weight honeycomb core and EPP foam. The research results provide a new idea for the design of crash box.