Modeling and characterizing the elastodynamic response of octet-truss lattice structures using resonance techniques. (February 2023)

• Record Type: Journal Article
• Authors: Fisher, Karl; Wang, Jenny; Tran, Brian
• Is Part Of: Materials & design. Volume 226(2023)
• Publication Date: 2023-02
• Subjects: Resonant ultrasound spectroscopy -- Particle swarm optimization -- Ti5553 -- Anisotropic elastic materials -- Lattice structures -- Laser powder bed fusion -- And additive manufacturing; Materials -- Periodicals; Engineering design -- Periodicals; Matériaux -- Périodiques; Conception technique -- Périodiques; Electronic journals; 620.11
• DOI: 10.1016/j.matdes.2023.111688
• Languages: English
• ISSNs: 0264-1275

Abstract

Graphical abstract: Highlights: Within the long wavelength limit, Resonant Ultrasound Spectroscopy (RUS) provides an alternative approach for determining the linear elastic properties of a lattice structure instead of the traditional quasi-static methods. Continuum approximations of lattice structures based on effective properties from RUS measurements facilitate accurate computationally efficient models. The effective elastic tensor of anisotropic lattice topologies can be determined with a single measurement sample. Abstract: Characterization of additively manufactured materials and structures is an ongoing effort for the advanced manufacturing community. This article will investigate an approach using resonant spectral ultrasound (RUS) to measure the effective elastic constants of an Octet Truss lattice and apply the results to continuum bases models representing the lattice regions in different structures. The study is focused on simple lattices structures fabricated from Ti5553 using a laser powder bed fusion process (LBPF). Solid and lattice samples are measured to determine RUS estimates for the elastic properties of the bulk material and the effective elastic properties of the lattice structure. The estimated elastic properties are then incorporated into 3d finite element models using a continuum approximation of the physical AM parts. Comparisons show good agreement between the experimentally measured eigen frequencies of the Ti5553 LBPF parts and the eigen frequencies calculated using the continuum approximations based on the effective RUS elastic properties. The current results suggest there is additional physics and geometrical effects that are accounted for in the RUS continuum approximation of the lattice that are not captured in the full 3d finite element model of the parts utilizing only the base material properties.