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  Open Access link: https://doi.org/10.1016/j.matdes.2022.111398

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Intercalation Hosts for Multivalent-Ion Batteries

Wiley Small Structures [Link]

The transition between necking-mediated tensile failure of glasses, at elevated temperatures

and/or low strain-rates, and shear-banding-mediated tensile failure, at low temperatures and/or

high strain-rates, is investigated using tensile experiments on metallic glasses and atomistic simula-

tions. We experimentally and simulationally show that this transition occurs through a sequence of

macroscopic failure patterns, parametrized by the ultimate tensile strength. Quantitatively analyz-

Understanding the fracture toughness of glasses is of prime importance for

science and technology. We study it here using extensive atomistic simulations in

which the interaction potential, glass transition cooling rate, and loading geometry

are systematically varied, mimicking a broad range of experimentally accessible

properties. Glasses’ non-equilibrium mechanical disorder is quantified through

A_g, the dimensionless prefactor of the universal spectrum of non-phononic

We developed an inverse design method for constructing 3D reconfigurable architected structures — we synthesized modular origami structures whose unit cells can be volumetrically mapped into a prescribed 3D curvilinear shape followed by volumetric shrinkage for constructing modules. After modification of tubular geometry, we searched modular origamis’ geometry and topology for target mobility using a topological reconstruction of modules.

Traditionally dynamic analysis is done using Newton’s universal laws of the equation of motion. According to the laws of Newtonian mechanics, the x, y, z, space-time coordinate system does not include a term for energy loss, an empirical damping term “C” is used in the dynamic equilibrium equation. Energy loss in any system is governed by the laws of thermodynamics. Unified Mechanics Theory (UMT) unifies the universal laws of motion of Newton and the laws of thermodynamics at ab-initio level.

The unified mechanics theory (UMT) is ab-initio unification of the second law of thermodynamics and Newton's universal laws of motion, in which Boltzmann's second law of entropy formulation governs dissipation & degradation. Hence, the unified mechanics theory does not require any empirical dissipation & degradation potential function or an empirical void evolution function. Material degradation is quantified on the Thermodynamic state index (TSI) axis based on the specific entropy production, which starts at zero and asymptotically approaches one at failure.

Abstract

The unified mechanics theory (UMT) was used to develop a model to predict the fatigue life of pre-corroded steel samples with BCC structure. Details of the experimental validation are also provided.

https://doi.org/10.1016/j.matdes.2022.111383

Boliang Wu, Tianzhen Liu, Yuzhen Chen and Lihua Jin