Structure-property relationship in honeycomb acoustic metamaterials for customizable low-frequency sound absorption

Abstract The pursuit of synergistic integration of structural load‐bearing, lightweight design, and vibroacoustic control remains a pivotal challenge in advanced engineering structures. While honeycomb‐based architectures offer a promising platform, a systematic understanding of how their intrinsic geometric symmetry governs acoustic performance has remained elusive, hindering targeted design. To fill this knowledge gap, this study presents the first comprehensive comparison of the acoustic behavior of three honeycomb‐core acoustic metamaterials (HAMs) with fundamental symmetries—hexagonal, square, and triangular—under identical normalized geometric and material parameters. Through an integrated methodology combining theoretical modeling, numerical simulation, and experimental validation, we elucidate how geometric symmetry fundamentally dictates impedance‐matching conditions and resonance‐mode evolution, leading to distinct acoustic outcomes: the hexagonal HAM achieves near‐perfect absorption at 253 Hz with balanced performance, the square counterpart attains a similar peak at 234 Hz, while the triangular HAM offers the widest half‐absorption bandwidth at elevated frequencies. Parametric analyses further demonstrate that key geometric parameters, especially cavity thickness, enable tailored acoustic tuning. The established structure‐property relationships not only provide mechanistic insights into symmetry‐governed sound absorption but also deliver practical design principles for selecting and optimizing honeycomb geometries according to specific performance targets, whether prioritizing peak absorption, broadband response, or manufacturability, in next‐generation lightweight structural‐acoustic systems.