Mechanical design and energy absorption performances of novel plate-rod hybrid lattice structures

Abstract

Hybrid lattice structures, integrating diverse structural components from fundamental lattice topologies, have attracted significant attention for their exceptional mechanical properties encompassing elastic modulus, yield stress, and energy absorption. To amalgamate the lightweight characteristics of rod structures with the robust mechanical properties of plate structures, a novel plate-rod hybrid lattice (PRHL) with controllable geometrical parameters and higher energy absorption was proposed and fabricated via the Selective Laser Sintering technique. In the PRHL design, the hybrid rod structure, interlinked with the center of each surface of the semi-open Octet plate lattice (SOPL), mutually provides support and deformation constraints. To identify the mechanical properties of PRHL, quasi-static uniaxial compression tests of PRHL samples sintered by Polylactic Acid powder were carried out. In comparison to SOPL, the newly proposed PRHL demonstrates an approximate 13.4% improvement in initial crush stress and an 18.5% increase in specific energy absorption capacity. Furthermore, numerical simulations incorporating the effect of printing orientation were performed to analyze the deformation mechanism of the PRHL structures. The present study also underscores the capacity to fine-tune the mechanical properties of PRHLs by regulating the plate thickness, rod diameter and excavated hole diameter.