Prediction and enhancement of dynamic response of 3D auxetic structure against impact load for vehicle crash box

This work focuses on the design, prediction, and enhancement of the dynamic response of a 3D auxetic structure for crash box applications. The objective is to optimize energy absorption and crashworthiness by employing a re-entrant honeycomb auxetic structure instead of a hollow crash box shell. Auxetic structures, characterized by a negative Poisson’s ratio, offer superior performance in crash scenarios due to their ability to dissipate energy efficiently while undergoing plastic deformation. Multilinear isotropic hardening was applied to simulate plastic zone deformation accurately. Following validation, a detailed crash box model was developed, incorporating real-world dynamic loading conditions. The auxetic core’s energy absorption characteristics, specific energy absorption, peak force, and load-displacement behavior were analysed through quasi-static simulations. The optimal combination of re-entrant angle, variable stiffness factor, and thickness has been identified from 12 different configurations using the Taguchi method. This study aims to contribute to the enhancement of crash box designs, offering insights into the use of auxetic structures to improve energy dissipation and crash resistance.