Sandwich structures with repairable cores based on truncated cube cells

Hedayati, R.; Yousefi, Armin; Bodaghi, Mahdi

doi:10.1016/j.compositesb.2022.110124

Sandwich structures with repairable cores based on truncated cube cells

Title

Sandwich structures with repairable cores based on truncated cube cells

Author

Hedayati, R. (TU Delft Novel Aerospace Materials)
Yousefi, Armin (Nottingham Trent University)
Bodaghi, Mahdi (Nottingham Trent University)

Date

2022

Abstract

With dramatic increase in 3D printing applications in industry, sandwich panels with 3D printed cores have gained a lot of attention recently. In harmony with global movement towards sustainability and low-carbon emission industries, sandwich panels with easy-to-repair and cost-effective cores would be very attractive structures. In this regard, implementing separated cells for constructing lattice structures instead of using back-to-back lattice structures makes repairing local damages in the core easier and more cost-effective. Ideally, a damaged cell can be replaced with an intact new cell without the need to change the whole core structure. In this study, mechanical responses of a single truncated cube unit cell, a well-known geometry for constructing regular lattices has been studied analytically, numerically, and experimentally. Analytical relationships were derived for stiffness, yield stress, and Poisson's ratio of a single unit cell. Samples were 3D printed and tested mechanically in large deformation regime. A good agreement between results from analytical derivations, numerical simulations, and experiments was observed. It was shown that an equilateral truncated cube structure has a yield stress at least twice of that for a simple cube structure. Three types of repairable sandwich panels with different uniform core densities as well as four graded cores were studied as well. The functionally graded sandwich panels presented the best performance while considering both energy absorption capacity and mass. The best functionally graded sandwich panels (Type 4) showed an increase in specific energy absorption (SEA) by almost 21% and a decrease in maximum displacement by 2.5% with respect to the second-ranking best option.

Subject

3D printing
Analytical solution
FEM
Repairable cores
Sandwich structures
Truncated cube

To reference this document use:

http://resolver.tudelft.nl/uuid:7a873865-041a-430f-be32-3dfd0d0ca7bf

DOI

https://doi.org/10.1016/j.compositesb.2022.110124

ISSN

1359-8368

Source

Composites Part B: Engineering, 243

Part of collection

Institutional Repository