The origin of the boundary strengthening in polycrystal-inspired architected materials

Abstract

Crystal-inspired approach is found to be highly successful in designing extraordinarily damage-tolerant architected materials. i.e. meta-crystals, necessitating in-depth fundamental studies to reveal the underlying mechanisms responsible for the strengthening in meta-crystals. Such understanding will enable greater confidence to control not only strength, but also spatial local deformation. In this study, the mechanisms underlying shear band activities were investigated and discussed to provide a solid basis for predicting and controlling the local deformation behaviour in meta-crystals. The boundary strengthening in polycrystal-like meta-crystals was found to relate to the interaction between shear bands and polygrain-like boundaries. More importantly, the boundary type and coherency were found to be influential as they govern the transmission of shear bands across meta-grains boundaries. The obtained insights in this study provide crucial knowledge in developing high strength architected materials with great capacity in controlling and programming the mechanical strength and damage path.

Porous single crystal niobium nitride and tantalum nitride nanocubes boost catalytic performance

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“…Generally, porous materials are polycrystals with many grain boundaries and defects, or non-crystals with disordered arrangement of atoms and without certain lattice constants. 34,35…”

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“…The load-bearing capacity of a structure has always been one of the criteria for evaluating the mechanical performance of a structure in practice, which makes damage and fracture play an important role in the study of structures (Ryvkin et al 2020;Ryvkin and Cherkaev 2021;Vangelatos et al 2020;Wu and Yang 2020;Zorzetto and Ruffoni 2017). At the same time, how to enhance the fracture resistance of a structure and improve the load-bearing capacity of the structure has been a problem that researchers are committed to explore (Liu et al 2021;Mueller and Shea 2018;Pham et al 2019). Recently, for lattice structures, the effect of negative Poisson's ratio on the fracture behavior of the structure has been studied (Li et al 2021;Nečemer et al 2019;Tomažinčič et al 2020).…”

Three Dimensional Printing of Bioinspired Crossed-Lamellar Metamaterials with Superior Toughness for Syntactic Foam Substitution

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