Design, FEM Analysis and Compression Tests on Energy-Absorbing Property of Disordered Cellular Solids Developed by 3D-Voronoi Division

Abstract

Lightweight cellular solids have been used as an energy-absorbing material for automotive and aerospace applications. Additive manufacturing is a useful process for the design and manufacture of cellular solids. The present study focuses on the relationship between the energy-absorbing property and the cell structure of additively manufactured porous aluminum alloys. Disordered cell structures with different regularity are designed by the technique of 3D-Voronoi division. Open-cell structures with a porosity of 90% and a strut diameter of 1 mm are generated using commercial 3D CAD software. Explicit FEM analysis including a Johnson-Cook failure model successfully simulates the compressive stress-strain curves of disordered porous aluminum alloys. Experimental results of compression tests were in good qualitative agreement with the FEM analysis. The ordered cell structure with high regularity is disadvantageous for energy-absorbing applications because of the formation of a macroscopic shear band. A slightly low cell regularity in a additively manufactured cellular solid is effective for increasing energy absorption.