Digital light processing of 2D lattice composites for tunable self-sensing and mechanical performance

Saadi, O. W., Uddin, M. A., Schiffer, A. and Kumar, S. (2023) Digital light processing of 2D lattice composites for tunable self-sensing and mechanical performance. Advanced Engineering Materials, (doi: 10.1002/adem.202300473) (Early Online Publication)

Abstract

This study investigates the mechanical and piezoresistive self-sensing performance of additive manufacturing-enabled 2D nanocomposite lattices under monotonic and cyclic tensile loading. Lattice structures comprising hexagonal, chiral, triangular, and re-entrant unit cell topologies are realized via Digital Light Processing (DLP) using an acrylic photocurable resin filled with carbon nanotubes (CNTs). The results reveal that the piezoresistive sensitivity of re-entrant and triangular lattices is nearly insensitive to changes in the relative density. In contrast, the gauge factors of the hexagonal and chiral lattices rose by 300 and 500%, respectively, with an increase in relative density from 20 to 40%, which can be ascribed to their bend-dominated behaviour, causing an increase in surface strains in the lattice struts with increasing relative density for an imposed macroscopic strain. The measured stress vs. strain responses compare well with nonlinear finite element results. Under strain-controlled cyclic loading, the electrical resistance of the 2D lattices is found to decline over time due to re-orientation of the CNTs in the surrounding viscoelastic polymer matrix. The findings provide valuable insights into the interrelations between sensing performance, cell architecture and relative density of the lattices, and offer guidelines for the design of architected strain sensors and self-sensing lightweight structures.

• Item Type: Articles
• Status: Early Online Publication
• Refereed: Yes
• Glasgow Author(s) Enlighten ID: Kumar, Professor Shanmugam
• Authors: Saadi, O. W., Uddin, M. A., Schiffer, A., and Kumar, S.
• College/School: College of Science and Engineering > School of Engineering > Systems Power and Energy
• Journal Name: Advanced Engineering Materials
• Publisher: Wiley
• ISSN: 1438-1656
• ISSN (Online): 1527-2648
• Published Online: 15 July 2023
• Copyright Holders: Copyright © 2023 Khalifa University of Science and Technology and The Authors
• First Published: First published in Advanced Engineering Materials 2023
• Publisher Policy: Reproduced under a Creative Commons License