In situ microscopy techniques for characterizing the mechanical properties and deformation behavior of two-dimensional (2D) materials

This chapter reviews recent development of graphene-based polymer composites. The formation of graphene oxide and graphene are a vital two dimensional (2D) material has received a lot of research interest in commercialization aspect due to its excellent electrical, thermal as well as mechanical properties at very low filler content. In this manner, utilization of graphene-based polymer composites with different polymer matrixes have been attracted increasing attention in recent years for both fundamental studies and applied research into industrial applications in many fields. Herein, novel properties of polymer (epoxy, polystyrene, and PANI) / graphene composites will be reviewed along with detailed examples drawn from the scientific literature. Keywords: Graphene-based polymer composites, thermo-mechanical properties, two dimensional (2D) materials

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Mechanical anisotropy of two-dimensional metamaterials: a computational study

Nanoscale Advances ◽

10.1039/c9na00312f ◽

2019 ◽

Vol 1 (8) ◽

pp. 2891-2900 ◽

Cited By ~ 1

Author(s):

Ning Liu ◽

Mathew Becton ◽

Liuyang Zhang ◽

Keke Tang ◽

Xianqiao Wang

Keyword(s):

Mechanical Properties ◽

Molecular Dynamics ◽

Molecular Dynamics Simulations ◽

Computational Study ◽

2D Materials ◽

Mechanical Anisotropy ◽

Coarse Grained ◽

Two Dimensional ◽

Geometrical Factors ◽

Dynamics Simulations

Mechanical properties, especially negative Poisson's, of 2D sinusoidal lattice metamaterials based on 2D materials depends highly on both geometrical factors and tuned mechanical anisotropy according to our generic coarse-grained molecular dynamics simulations.

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Two-Dimensional Mapping of the Mechanical Properties of Pb-Free Solders for Reliability Optimization

Journal of Microelectronics and Electronic Packaging ◽

10.4071/1551-4897-6.3.182 ◽

2009 ◽

Vol 6 (3) ◽

pp. 182-185

Author(s):

V. Marques ◽

C. Johnston ◽

P.S. Grant

Keyword(s):

Mechanical Properties ◽

Solder Joint ◽

Elevated Temperatures ◽

Constitutive Models ◽

Processing Temperature ◽

Reliability Optimization ◽

Two Dimensional ◽

Free Solder ◽

Dimensional Mapping

The development of thermomechanical models of Pb-free solders is more complex than for Pb-Sn solders as a result of their higher reactivity and processing temperature that leads to the continuous evolution of stiff and angular intermetallics in the microstructure. In this paper, nanoindentation has been explored for its potential to characterize mechanically the complex microstructure of Pb-free solder joints. Hardness and Young's modulus of the various microphases in a Sn-Ag-Cu/Cu solder joint were characterized at 25°C and averages were obtained from nanoindentation maps composed of 100–200 indentations. The possibility to map mechanical property gradients across the various solder joint interfaces and to differentiate between different presentations of the same phase, including in situ at elevated temperatures, has been suggested to be useful in extending the available data for constitutive models used in reliability simulations of Pb-free solders.

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Thermo-mechanical correlation in Two-dimensional materials

Nanoscale ◽

10.1039/d0nr06824a ◽

2021 ◽

Author(s):

Yuan Cheng ◽

Xing Wu ◽

Zijian Zhang ◽

Yao Sun ◽

Yunshan Zhao ◽

...

Keyword(s):

Mechanical Properties ◽

2D Materials ◽

Research Community ◽

Two Dimensional ◽

The Past ◽

Physical Chemical ◽

Two Dimensional Materials

Two-dimensional (2D) materials have received tremendous attention from the research community in the past decades, because of their numerous striking physical, chemical and mechanical properties and promising potential in a...

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Effect of Cellulose Microfiber Silylation Procedures on the Properties and Antibacterial Activity of Polydimethylsiloxane

Coatings ◽

10.3390/coatings10060567 ◽

2020 ◽

Vol 10 (6) ◽

pp. 567

Author(s):

Virginija Jankauskaitė ◽

Aistė Balčiūnaitienė ◽

Radostina Alexandrova ◽

Nijolė Buškuvienė ◽

Kristina Žukienė

Keyword(s):

Mechanical Properties ◽

Vapor Phase ◽

Chemical Reduction ◽

Antibacterial Properties ◽

Crosslinking Density ◽

Gram Negative Bacteria ◽

Gram Negative ◽

Cellulose Microfibers ◽

Microscopy Techniques

In this study, the liquid phase and vapor phase procedures for silylating cellulose microfibers by hexamethyldisilazane (HMDS) were compared in terms of efficiency. The influence of functionalization degree on the morphology of microfibers and their interaction with polydimethylsiloxane (PDMS) matrix has been investigated. The antibacterial properties of silylated cellulose microfibers hybridized with Ag nanoparticles, obtained by in situ chemical reduction, were also studied. Sample morphology investigations were carried out using spectroscopy and microscopy techniques (FTIR, XPS, TEM, SEM, EDS, XPS). Trimethylsilyl moieties appear on the surface of the cellulose microfibers after modification and improve the dispersibility of the microfibers, allowing strong interaction with the PDMS matrix and favoring its crosslinking density. Microfibers functionalized by the vapor phase of HMDS show smoother surfaces with higher concentrations of Si-containing groups, resulting in a more hydrophobic wetting behavior and a greater influence on the mechanical properties of the polymer. The silylated cellulose microfiber–Ag nanohybrid shows stronger antimicrobial activity towards Gram-positive and Gram-negative bacteria strains compared to that of the untreated hybrid. A PDMS composite loaded with this hybrid exhibits the ability to inhibit bacterial growth.

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Interaction of gases with monolayer WS2: An In Situ Spectroscopy Study

Nanoscale ◽

10.1039/d1nr01483h ◽

2021 ◽

Author(s):

Rahul Rao ◽

Hyunil Kim ◽

Nestor Perea Lopez ◽

Mauricio Terrones ◽

Benji Maruyama

Keyword(s):

2D Materials ◽

Chemical Adsorption ◽

In Situ Spectroscopy ◽

Two Dimensional ◽

Spectroscopy Study ◽

Sensor Platforms ◽

Optical And Electronic Properties ◽

Adsorption Of Gases ◽

Physical And Chemical

The optical and electronic properties of two-dimensional (2D) materials can be tuned through physical and chemical adsorption of gases. They are also ideal sensor platforms, where charge transfer from the...

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In Situ Nanoscale Deformation Studies on Micro Copper Wires Using Atomic Force Microscopy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.97-101.4197 ◽

2010 ◽

Vol 97-101 ◽

pp. 4197-4200

Author(s):

Bo Wen Zhang ◽

Yong Da Yan ◽

Zhen Jiang Hu ◽

Xue Sen Zhao ◽

Ying Chun Liang ◽

...

Keyword(s):

Mechanical Properties ◽

Deformation Behavior ◽

Deformation Process ◽

Failure Strain ◽

Copper Wire ◽

Separation Process ◽

Single Crystal Copper ◽

Force Microscopy ◽

Atomic Force

As the dimensions of parts become smaller, understanding the mechanical properties of these small components was becoming more important. Till present day, the methods and technology used to investigate the deformation behavior in nanoscale were still lacking. In this paper, the specimens were single crystal copper wires with diameter in 50 microns. Atomic force microscope integrated with an in- situ tensile system were used to determine the mechanical behavior of copper wires and observe the surface topography deformation in nanoscale simultaneously. The results were as follows: the modulus of elasticity, tensile strength and failure strain of the sample were 167Gpa, 0.564GPa and 0.011, respectively. By using AFM, the separation process between the copper wire and impurities on it, such as oxide film, was observed. The nanoscale deformation process of the copper wire was also obtained.

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An In Situ Reflectance Spectroscopic Investigation to Monitor Two-Dimensional MoS2 Flakes on a Sapphire Substrate

Materials ◽

10.3390/ma13245794 ◽

2020 ◽

Vol 13 (24) ◽

pp. 5794

Author(s):

Yina Wang ◽

Lei Zhang ◽

Wen Yang ◽

Shanshan Lv ◽

Chenhui Su ◽

...

Keyword(s):

Dielectric Constant ◽

2D Materials ◽

Chemical Vapor ◽

Reflectance Spectroscopy ◽

In Situ Monitoring ◽

Structure Evolution ◽

Two Dimensional ◽

Characteristic Peak ◽

Non Destructive

In this work, we demonstrate the application of differential reflectance spectroscopy (DRS) to monitor the growth of molybdenum disulfide (MoS2) using chemical vapor deposition (CVD). The growth process, optical properties, and structure evolution of MoS2 were recorded by in-situ DRS. Indeed, blue shifts of the characteristic peak B were discussed with the decrease of temperature. We also obtained the imaginary part of the MoS2 dielectric constant according to reflectance spectra. This method provides an approach for studying the change of two-dimensional (2D) materials’ dielectric constant with temperature. More importantly, our work emphasizes that the DRS technique is a non-destructive and effective method for in-situ monitoring the growth of 2D materials, which is helpful in guiding the preparation of 2D materials.

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Analytical models for predicting the nonlinear stress-strain relationships and behaviors of two-dimensional carbon materials

Journal of Applied Mechanics ◽

10.1115/1.4050689 ◽

2021 ◽

pp. 1-59

Author(s):

Zixin Xiong ◽

Teng Zhang ◽

Xiaoyan Li

Keyword(s):

Mechanical Properties ◽

Elastic Constants ◽

2D Materials ◽

Analytical Models ◽

Two Dimensional ◽

Stress Strain ◽

Angle Variation ◽

Nonlinear Stress ◽

And Behaviors ◽

Strain Responses

Abstract Due to having a single atom layer, two-dimensional (2D) materials represented by graphene monolayers exhibit unique and excellent mechanical properties, such as ultrahigh moduli and strengths. A large number of experiments and atomistic simulations have demonstrated nonlinear stress-strain responses. However, there is no theoretical model that analytically describes the nonlinear stress-strain relationships and relevant material properties of 2D materials. Here we developed a nonlinear stick-spiral model for four typical 2D materials (including graphene, γ-graphyne, β-graphyne and hexagonal boron nitride) based on a molecular mechanics model. By using the perturbation method, we derived a series of analytical expressions for nonlinear stress-strain relationships and elastic constants of these 2D materials under uniaxial tension along the zigzag and armchair directions. Our analytic models indicated that both Young's moduli and Poisson's ratios of these 2D materials are isotropic and dominate the linear elastic deformation, while their third-order moduli are orientation-dependent and essentially characterize the nonlinear stress-strain responses. The nonlinear stress-strain relationships, elastic constants and atomic behaviors (such as bond elongation and bond angle variation during deformation) predicted from our analytical models are in good agreement with those from molecular dynamics simulations and previous experiments. Our analytical models further demonstrated that the mechanical properties and behaviors of 2D materials are linked with their bonding and atomic structures (from a quantitative perspective) and are mainly determined by the stiffnesses for bond stretching, angle variation and bond lengths.

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