Correlation Studies of Different Decoupled Two-Scale Simulations for Lattice Structures

By deliberately designing microscopic internal mechanisms, architected materials can achieve a variety of material properties without changing constituent materials. Integration of the architected materials into a structure as substructures has a good potential to enhance structural performance and realize wide design freedom. This paper explores the capabilities of multiscale approaches for lattice structures, which is a major mechanism in architected materials. The objectives of this paper are (1) to demonstrate the capabilities of the framework to evaluate stiffness characteristics of lattice structures with two different two-scale analysis approaches and (2) to assess the accuracies and validity ranges of both approaches for appropriate evaluations of lattice structures. The two-scale analysis framework consists of the computational homogenizations for the generalized stiffness (ABD) and 3D stiffness (C) matrices. Equivalent stiffness characteristics of the unit cell are obtained by computational homogenizations to effectively capture the macroscopic responses of lattice structures. This study provides a comprehensive correlation study between the prediction accuracies of the two-scale analysis approaches in terms of tensile, bending, and torsional stiffness characteristics for practical modeling and development of lattice structures. The study will contribute a guideline for effective designs of high-performance structures with architected materials.