Marine mussel plaque-inspired super soft, ductile and tough lattices

Abstract

The rise of soft materials and additive manufacturing has provided the feasibility of developing elastomer lattices for various engineering applications. Although earlier attempts have been made to manufacture and test the elastomer lattices, a comprehensive understanding of their fracture behaviour has remained elusive. Inspired by the soft foams in mussel plaque core, the present study introduces the concept of soft, ductile, and tough elastomer lattices. Uniaxial and planar tension tests were conducted, and numerical models were developed to facilitate data interpretation. The applicability of planar tension for measuring the fracture energy of elastomer lattices was confirmed through tensile tests using samples with various crack lengths and double-peeling tests. In addition, the fracture energy of the elastomer lattices was sensitive to volume fraction but insensitive to initial crack length, thickness, and height. Notably, two distinct failure modes, truss failure and joint failure, were correlated with volume fraction. The specimens that failed at the transition between these two failure modes achieve a higher fracture energy. This study provides new insights to the materials science community and provides a foundation for the development of lightweight, damage-tolerant, and high-performance metamaterials.