Determination of the effective elastic properties of titanium lattice structures

Abstract

This work aims at proposing a numerical approach to predict the mechanical response of lattice structures fabricated by means of a suitable additive layer manufacturing (ALM) process. The numerical procedure makes use of an explicit description of the lattice representative volume element (RVE) to investigate and compare the influence of the lattice RVE topology on the macroscopic elastic response. The proposed method is based on a general numerical homogenization scheme to determine the effective elastic properties of the lattice RVE at the macroscopic scale. A large numerical campaign has been conducted on 17 geometries. The effect of the RVE local features, e.g., the presence of a fillet radius and/or of a spherical node between struts composing the RVE as well as the surface roughness, on the effective elastic properties is investigated. Results show that both the relative density and the geometrical features of the RVE strongly affect the equivalent macroscopic elastic behavior of the lattice.

Keywords:

• Additive manufacturing
• finite element method
• homogenization
• lattice structure
• anisotropy