0
research-article

Impact of the Lattice Angle on The Effective Properties of The Octet-truss Lattice Structure

[+] Author and Article Information
Mohamed Abdelhamid

York University, Department of Mechanical Engineering, Lassonde School of Engineering, York University, 4700 Keele St., Toronto M3J 1P3, Ontario, Canada
mahamid@yorku.ca

Aleksander Czekanski

York University, Department of Mechanical Engineering, Lassonde School of Engineering, York University, 4700 Keele St., Toronto M3J 1P3, Ontario, Canada
alex.czekanski@lassonde.yorku.ca

1Corresponding author.

ASME doi:10.1115/1.4040409 History: Received October 01, 2017; Revised May 23, 2018

Abstract

Cellular materials are found extensively in nature such as wood, honeycomb, butterfly wings and foam-like structures like trabecular bone and sponge. This class of materials proves to be structurally-efficient by combining low weight with superior mechanical properties. Recent studies have shown there are coupling relations between the mechanical properties of cellular materials and their relative density. Due to its favorable stretching-dominated behavior, continuum models of the octet-truss were developed to describe its effective mechanical properties. However, previous studies were only performed for the cubic symmetry case where the lattice angle ?=45°. In this work, we study the impact of the lattice angle on the effective properties of the octet-truss: namely the relative density, effective stiffness, and effective strength. The relative density formula is extended to account for different lattice angles up to a higher order of approximation. Tensor transformations are utilized to obtain relations of the effective elastic, shear moduli, and Poisson's ratio at different lattice angles. Analytical formulas are developed to obtain the loading direction and value of the maximum and minimum specific elastic moduli at different lattice angles. In addition, tridimensional polar representations of the macroscopic strength of the octet-truss are analyzed for different lattice angles. Finally, collapse surfaces for plastic yielding and elastic buckling are investigated for different loading combinations at different lattice angles. It has been found that lattice angles lower than 45° result in higher maximum values of specific effective elastic moduli, shear moduli, and strength.

Copyright (c) 2018 by ASME
Your Session has timed out. Please sign back in to continue.

References

Figures

Tables

Errata

Discussions

Some tools below are only available to our subscribers or users with an online account.

Related Content

Customize your page view by dragging and repositioning the boxes below.

Related Journal Articles
Related eBook Content
Topic Collections

Sorry! You do not have access to this content. For assistance or to subscribe, please contact us:

  • TELEPHONE: 1-800-843-2763 (Toll-free in the USA)
  • EMAIL: asmedigitalcollection@asme.org
Sign In