Quasi-Static Crush and Energy Absorption Behavior of Additively Manufactured Honeycomb Structures with Buckling Initiators

To enhance the crashworthiness of hexagonal honeycomb structures under crush, this study investigated a method to reduce the initial peak collapse stress without reducing plateau stress. This was accomplished by implementing buckling initiators (BIs) in hexagonal honeycomb structures. These BIs facilitate a smoother transition from the initial linear elastic phase to the plateau stress region. For fabrication, additive manufacturing, specifically 3D printing, was employed, using acrylonitrile-butadiene-styrene (ABS) 3D filament to produce hexagonal honeycomb structures both with and without BIs. Experimental stress-strain curves were meticulously measured using an MTS machine. This empirical data then allowed for the calculation of key crashworthiness metrics: mean crush stress, energy absorption efficiency, and crush efficiency. The study systematically investigated how variations in BI size, height placement, and geometric pattern influenced the overall crashworthiness performance or crush behavior of the hexagonal honeycomb structures.