• A multifunctional lattice-honeycomb hybrid sandwich metastructure is proposed for impact resistance and thermal dissipation. • The multifunctional performance of sandwich metastructure is attributed to arch ratio. • A COPRAS method was proposed to evaluate the comprehensive performance. • The multifunctional performance of sandwich metastructure was investigated through experimental and numerical methods. Simultaneous enhancement of impact resistance and heat dissipation remains a critical bottleneck in the design of advanced metastructures. Drawing on inspiration from arch bridges, this work proposes a multifunctional sandwich metastructure. Two configurations “Honeycomb-Arch Lattice-Honeycomb” (HAH) and “Honeycomb-Symmetry Arch Lattice-Honeycomb” (HSAH) were developed to optimize the trade-off between structural protection and thermal efficiency. The impact resistance and heat dissipation performance of HAH and HSAH, across different arch ratios, were systematically evaluated. Assessment was performed using the Complex Proportional Assessment (COPRAS) method, based on residual velocity ( v ), peak crushing force ( PCF ), Nusselt number ( Nu ), friction factor ( f) , and pressure drop ( ΔP ). Configurations with a/b = 1.5 and c/d = 1.1 or 1.3 show the highest comprehensive evaluation scores ( Qi ). When applied to the equipment compartment floor of high-speed trains, the maximum impact stress decreased from over 500 MPa in the original corrugated structure to below 300 MPa. The v of steel sphere after impact decreased sharply. Crucially, the design also excelled in thermal management, yielding a 25%-31% reduction in equipment surface temperature. Overall, the proposed sandwich metastructure offers substantial improvements in both impact resistance and thermal management, offering a new paradigm for multifunctional design.
Zhao et al. (2026) studied this question.