Influence of geometric parameters on 3D periodic lattice effective properties

Lattice materials are generated by tessellating a unit cell, composed of a specific truss configurations, in an infinite periodicity to combine the effect of bulk material properties and geometric periodicity. They offer enhanced mechanical and dynamic properties per unit mass, and the ability to engineer the material response by optimizing the unit cell. Characterizing lattice properties through experiments can be a time consuming and costly process, so analytical and numerical methods are crucial. Specifically, the Bloch-wave homogenization approach allows one to characterize the effective static properties of the lattice unit cell while simultaneously analyzing wave propagation properties. While this analysis has been used for some time, a thorough study of this approach on 3D lattice materials with different symmetries and geometries is presented here. Using Bloch-wave homogenization, multiple periodic lattices with cubic, transversely isotropic, and tetragonal symmetry, including an auxetic geometry, over a wide range of relative densities are analyzed within a finite element framework. The effect of geometric parameters on lattice properties is discussed and a comparison between lattices based on their anisotropy index is presented. Method studied in this thesis can be extended for designing multifunctional metamaterials with optimized static and dynamic properties simultaneously. This work can also serve as the basis for nondestructive evaluation of metamaterials properties using ultrasonic velocity measurements.

Name thesis:degree_name

M.S.

Level thesis:degree_level

Thesis

Discipline thesis:degree_discipline

Mechanical Engineering

Grantor

University of Illinois at Urbana-Champaign

Year dc:date

2019

Author dc:creator

• Patil, Ganesh

Contributors dc:contributor

• Matlack, Kathryn H

• Lattices
• Bloch-wave
• Universal Anisotropy Index
• Anomalous Polarization
• Effective Properties
• Tetragonal Symmetry

Statement dc:rights

• Copyright 2019 Ganesh Patil

Language dc:language

en

Handle dc:identifier

http://hdl.handle.net/2142/105092

OAI identifier oai:identifier

oai:www.ideals.illinois.edu:2142/105092