A Surface-Enabled Computational Homogenization Method for Variable-Density Polymer Lattice Metastructures

The current limitations in predicting mechanical properties arise from an incomplete understanding of surface-induced size effects in variable-density polymer lattice metastructures. Through large-scale, high-fidelity finite element simulations, we identify a novel variable-density surface law governing the surface intrinsic length at the macroscopic scale. Capitalizing on this surface law discovery, we propose a surface-enhanced computational homogenization framework. By incorporating the surface intrinsic length parameters with the variable-density surface law and an offline database constructed through high-throughput numerical simulations, we develop an efficient predictive model capable of online analysis for the mechanical behavior of variable-density polymeric lattice metastructures. This innovative approach preserves critical configuration-dependent surface effects while achieving both efficiency and precision in predicting the macro-scale mechanical performance of such metastructures.