Simulation of the Compression Testing of Additively Manufactured Lattice Structures Using Inputs from Microcomputed Tomography

Abstract

Finite element (FE) modeling is a powerful tool for the virtual testing of components, especially for high-value manufacturing like additive manufacturing (AM). AM often involves lattice structures in parts, imparting unique mechanical properties. Numerical models allow for cost-effective virtual testing, but computational limitations hinder comprehensive investigations on lattice structures, and idealized models may not fully represent actual manufactured behavior. This study proposes a simplified numerical model for analyzing lattice structure compression behavior before failure, incorporating X-ray microcomputed tomography (CT) scan data. The model includes real manufacturing defects, such as geometrical inaccuracies, internal porosity, and surface roughness. It closely fits compression test results from samples with varied defects, with a maximum error of 17% for stiffness, 13% for yield stress, and 7% for peak stress. The model offers promise for developing manufacturing defect-incorporated lattice representative volume elements (RVEs) to design AM parts with lattice regions. Replacing complex lattice structures with solid-infilled RVEs in simulations reduces computational costs significantly. This approach allows efficient exploration of lattice AM components' mechanical behavior, accounting for manufacturing defects and offering insights for design optimization and material selection.