•We study the effects of lattice orientation on intragranular void growth.•We compare results from two crystal plasticity full-field models.•Effects of triaxiality and stress vs. strain-controlled ...conditions are discussed.•Voids in the hardest crystals grow the fastest in strain-rate controlled conditions.•In polycrystals, orientation effects on void growth strengthen with triaxiality.
In this work, we study the effect of crystallographic orientation and applied triaxiality on the growth of intragranular voids. Two 3D full-field micromechanics methods are used, the dilatational visco-plastic fast-Fourier transform (DVP-FFT) and the crystal plasticity Finite Elements (CP-FE), both of which incorporate a combination of crystalline plasticity and dilatational plasticity. We demonstrate with several select cases that predictions of void growth from both formulations agree qualitatively. With the more computationally efficient DVP-FFT, additional effects of polycrystalline microstructure and the influence of nearest neighborhood are investigated. Crystals bearing a single intracrystalline void are studied in three types of 3D microstructural environments: isolated single crystals, individual equal-sized grains within a regular polycrystal, and individual variable sized grains within a polycrystal with grains and voids randomly located. We show that loading type plays a significant role. In strain-rate controlled conditions, voids in the hardest 111-crystals grow the fastest in time, whereas in stress-controlled conditions, voids in the softest 100-crystal grow the fastest in time. The analysis reveals that on average void growth is slower for the same starting orientation in the polycrystal than in the single crystal. We find that at the highest triaxiality tested that the correlation between crystal orientation and void growth rate in the polycrystal strengthens, drawing closer to that seen in the isolated single crystals. These results and model can help guide the microstructural design of polycrystalline materials with high strength and damage-tolerance in high-rate deformation.
The earliest microwave absorbing materials (MAMs) are fabricated in the early 20th century for military purpose to inhibit radar detection. Currently, the application of MAMs has been existing in ...every part of human's life to prevent radiation and interference. The microwave absorbant and microwave absorbing coatings classified by composition including alloys, metal oxides, conductive polymers, carbon materials, ceramic materials both in traditional and innovative forms are introduced in this work. Considering the harsh and complex application environment, MAMs with high temperature resistance and infrared-compatible stealth performance are involved. Metamaterials, showing excellent electromagnetic properties which are far beyond that of the materials can achieve, including perfect absorber, digitally coded control metamaterials, bionic structural materials, and adjustable smart metamaterials, are also introduced specifically in this work. In addition, to investigate electromagnetic response of absorbant, the first-principles calculations works are overviewed. The electromagnetic properties, loss mechanisms, structure, fabrication method, regulation approaches, designing principles, current applications, and future prospects of MAMs are involved in this work. This work gives a comprehensively overview over the MAMs for their theoretical and experimental advances in recent years including the military radar (frequency range of 2–18 GHz) stealth materials, relevant infrared compatible (infrared-visible, infrared-radar, infrared-laser) stealth materials, and other stealth materials with multifrequency adaptability.
Engineered Living Hydrogels Liu, Xinyue; Inda, Maria Eugenia; Lai, Yong ...
Advanced materials (Weinheim),
July 1, 2022, Letnik:
34, Številka:
26
Journal Article
Recenzirano
Living biological systems, ranging from single cells to whole organisms, can sense, process information, and actuate in response to changing environmental conditions. Inspired by living biological ...systems, engineered living cells and nonliving matrices are brought together, which gives rise to the technology of engineered living materials. By designing the functionalities of living cells and the structures of nonliving matrices, engineered living materials can be created to detect variability in the surrounding environment and to adjust their functions accordingly, thereby enabling applications in health monitoring, disease treatment, and environmental remediation. Hydrogels, a class of soft, wet, and biocompatible materials, have been widely used as matrices for engineered living cells, leading to the nascent field of engineered living hydrogels. Here, the interactions between hydrogel matrices and engineered living cells are described, focusing on how hydrogels influence cell behaviors and how cells affect hydrogel properties. The interactions between engineered living hydrogels and their environments, and how these interactions enable versatile applications, are also discussed. Finally, current challenges facing the field of engineered living hydrogels for their applications in clinical and environmental settings are highlighted.
The convergence of engineering, biology, and materials science is providing unprecedented opportunities to integrate living microbes into hydrogel matrices. This integration constructs engineered living hydrogels with the capability of performing tasks associated with living microbes such as self‐replication, self‐adaption, and environmental responsiveness.
This review will present a comprehensive view of the field of stimuli-responsive healable materials. It will begin with an examination of the healing of polymeric materials, briefly discussing the ...conventional techniques for repair and maintenance of composite materials. It will continue with a detailed analysis of the various systems that have been proposed and investigated over the past two decades, with particular emphasis on work published in the past two years. These systems will be introduced according to the particular stimulus responsible for initiation of healing to occur, moving from mechanical damage to heat, electricity, electromagnetic field, ballistic impact, and light. This discussion will cover the work done in the early days of healable materials, and will include current trends and potential future directions.
As a two-dimensional (2D) material, graphene shows excellent advantages in the field of gas sensors due to its inherent large specific surface area and unique electrical properties. However, in the ...practical application of gas detection, graphene sheet is easy to form irreversible agglomeration and has some limitations such as low sensitivity, long response time and slow recovery speed, which greatly reduce its gas sensing performance. As a gas sensing material, three-dimensional (3D) porous graphene has been extensively studied in recent years owing to its larger specific surface area and stable structure. In order to synthesize graphene with different three-dimensional structures, many methods have been developed. Herein, the synthesis and assembly of three-dimensional graphene and its composites were reviewed, with emphasis on the application of three-dimensional graphene and its composites in the field of gas sensors. The challenges and development prospects of three-dimensional graphene materials in the application of gas sensors were briefly described.
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