New auxetic materials with stretch-dominant architecture using simple trusses

Abstract

Cellular auxetic materials, as a group of metamaterials, have received much interest due to their promising mechanical properties in various applications. The main shortcomings of cellular auxetic materials are their low stiffness and strength, due to a bending-dominant architecture. Here, a novel concept to design auxetic stretch-dominated structures is presented. Three example structures are analyzed in detail, to demonstrate the tunability and extensive range of positive and negative Poisson’s ratio for these structures. Results show that the relative stiffnesses of the three test structures are several times higher than those of previously reported auxetic structures, for example, reentrant models.

Keywords:

• Auxetic materials
• enhanced stiffness
• finite element analysis
• stretch-dominated
• 3D printing

Additional information

Funding

This research was supported by Brain Pool program funded by the Ministry of Science and ICT through the National Research Foundation of Korea (NRF-2019H1D3A2A01062181). This work was partly supported by a National Research Foundation of Korea (NRF) grant funded by the Korea government (MSIT) (No. 2020R1A5A6017701) for which the last author of this article (W.-Ry. Yu) feels grateful.