Direct Tensile Tests of Individual WS2 Nanotubes

2005 ◽  
Vol 475-479 ◽  
pp. 4097-4102 ◽  
Author(s):  
I. Kaplan-Ashiri ◽  
S.R. Cohen ◽  
K. Gartsman ◽  
R. Rosentsveig ◽  
V. Ivanovskaya ◽  
...  
Keyword(s):  
Young’S Modulus ◽  
Young's Modulus ◽  
Tight Binding ◽  
Md Simulations ◽  
Tensile Tests ◽  
Average Value ◽  
Atomic Force ◽  
Direct Tensile ◽  
Single Wall Nanotubes ◽  
Good Agreement

The Young’s modulus of WS2 nanotubes is an important property for various applications. Measurements of the mechanical properties of individual nanotubes are challenging because of the small size of the tubes. Lately, measurements of the Young’s modulus by buckling of an individual nanotube using an atomic force microscope1 resulted in an average value of 171GPa. Tensile tests of individual WS2 nanotubes were performed experimentally using a scanning electron microscope and simulated tensile tests of MoS2 nanotubes were performed by means of a densityfunctional tight-binding (DFTB) based molecular dynamics (MD) scheme. Preliminary results for WS2 nanotubes show Young’s modulus value of ca.162GPa, tensile strength value of ca. 13GPa and average elongation of ca. 12%. MD simulations resulted in elongation of 19% for zigzag and 17% for armchair MoS2 single wall nanotubes. Since MoS2 and WS2 nanotubes have similar structures the same behavior is expected for both, hence there is a good agreement regarding the elongation of WS2 nanotubes between experiment and simulation.

Mechanical behavior of individual WS2 nanotubes

2004 ◽  
Vol 19 (2) ◽  
pp. 454-459 ◽  
Author(s):  
I. Kaplan-Ashiri ◽  
S.R. Cohen ◽  
K. Gartsman ◽  
R. Rosentsveig ◽  
G. Seifert ◽  
...  
Keyword(s):  
Mechanical Behavior ◽  
Young’S Modulus ◽  
Density Functional ◽  
Young's Modulus ◽  
Bulk Material ◽  
Tight Binding ◽  
Atomic Force ◽  
Silicon Cantilever ◽  
Microscope Imaging ◽  
Single Wall Nanotubes

The Young's modulus of WS2 nanotubes is an important property for various applications. Measurements of the mechanical properties of individual nanotubes are challenged by their small size. In the current work, atomic force microscopy was used to determine the Young's modulus of an individual multiwall WS2 nanotube, which was mounted on a silicon cantilever. The buckling force was measured by pushing the nanotube against a mica surface. The average Young's modulus of an individual WS2 nanotube, which was calculated by using Euler's equation, was found to be 171 GPa. First-principle calculations of the Young's modulus of MoS2 single-wall nanotubes using density-functional–based tight-binding method resulted in a value (230 GPa) that is close to that of the bulk material. Furthermore, the diameter dependence of the Young's modulus in both zigzag and armchair configuration was studied and was found to approach the bulk value for nanotubes with few-nanometer diameters. Similar behavior is expected for WS2 nanotubes. The mechanical behavior of the WS2 nanotubes as atomic force microscope imaging tips gave further support for the measured Young's modulus.

scholarly journals Atomic Simulation of Nanoindentation on the Regular Wrinkled Graphene Sheet

Materials ◽  
2020 ◽  
Vol 13 (5) ◽  
pp. 1127
Author(s):  
Ruonan Wang ◽  
Haosheng Pang ◽  
Minglin Li ◽  
Lianfeng Lai
Keyword(s):  
Mechanical Properties ◽  
Boundary Condition ◽  
Boundary Conditions ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Md Simulations ◽  
Force Microscopy ◽  
Atomic Simulation ◽  
Atomic Force ◽  
Surface Wrinkling

Surface landscapes have vague impact on the mechanical properties of graphene. In this paper, single-layered graphene sheets (SLGS) with regular wrinkles were first constructed by applying shear deformation using molecular dynamics (MD) simulations and then indented to extract their mechanical properties. The influence of the boundary condition of SLGS were considered. The wrinkle features and wrinkle formation processes of SLGS were found to be significantly related to the boundary conditions as well as the applied shear displacement and velocity. The wrinkling amplitude and degree of wrinkling increased with the increase in the applied shear displacements, and the trends of wrinkling wavelengths changed with the different boundary conditions. With the fixed boundary condition, the degree of graphene wrinkling was only affected when the velocity was greater than a certain value. The effect of wrinkles on the mechanical characterization of SLGS by atomic force microscopy (AFM) nanoindentation was finally investigated. The regular surface wrinkling of SLGS was found to weaken the Young’s modulus of graphene. The Young’s modulus of graphene deteriorates with the increase in the degree of regular wrinkling.

scholarly journals Тестирование на изгиб наноразмерных консолей в атомно-силовом микроскопе

2022 ◽  
Vol 48 (3) ◽  
pp. 24
Author(s):  
А.В. Анкудинов ◽  
М.М. Халисов
Keyword(s):  
Atomic Force Microscope ◽  
Young’S Modulus ◽  
Elastic Foundation ◽  
Test Data ◽  
Young's Modulus ◽  
Atomic Force ◽  
Good Agreement

Consoles and bridges of MgNi2Si2O5(OH)4 nanoscrolls were tested for bending in atomic force microscope. Using test data, we analyze how the consoles or bridges were fixed, and took this information into account when calculating the Young's modulus of the nanoscrolls. The results on the consoles are in good agreement with the results on the bridges when modeling the latter as three-span beams, and the former as beams on an elastic foundation with a suspended console.

Ultrasonically synthesized organic liquid-filled chitosan microcapsules: part 2: characterization using AFM (atomic force microscopy) and combined AFM–confocal laser scanning fluorescence microscopy

Soft Matter ◽  
2018 ◽  
Vol 14 (16) ◽  
pp. 3192-3201 ◽  
Author(s):  
Srinivas Mettu ◽  
Qianyu Ye ◽  
Meifang Zhou ◽  
Raymond Dagastine ◽  
Muthupandian Ashokkumar
Keyword(s):  
Atomic Force Microscopy ◽  
Fluorescence Microscopy ◽  
Young’S Modulus ◽  
Laser Scanning ◽  
Young's Modulus ◽  
Organic Liquid ◽  
Confocal Laser Scanning ◽  
Confocal Laser ◽  
Force Microscopy ◽  
Atomic Force

Atomic Force Microscopy (AFM) is used to measure the stiffness and Young's modulus of individual microcapsules that have a chitosan cross-linked shell encapsulating tetradecane.

Cellulose Whiskers Micro-Fibers Effect in the Mechanical Proprieties of PP and PLA Composites Fibers Obtained by Spinning Process

2011 ◽  
Vol 146 ◽  
pp. 12-26 ◽  
Author(s):  
A. Gherissi ◽  
R.Ben Cheikh ◽  
E. Dévaux ◽  
Fethi Abbassi
Keyword(s):  
Mechanical Properties ◽  
Young’S Modulus ◽  
Volume Fraction ◽  
Young's Modulus ◽  
Tensile Tests ◽  
Advanced Materials ◽  
Uniaxial Tensile ◽  
Failure Resistance ◽  
Cellulose Whiskers ◽  
Limit Strength

In this study, we present the manufacturing process of two new composites materials in the form of long fibers of polylactic-acid (PLA) or polypropylene (PP), reinforced by cellulose whiskers micro-fibers loads. In order to evaluate the mechanical properties of these advanced materials, a several uniaxial tensile tests were carried out. The PP and the PLA have initially been spinning without the addition of cellulose whiskers micro-fibers. In order to study the effects of cellulose whiskers micro-fibers reinforcements in the Mechanical behavior of the PLA and PP filaments, we determinate the proprieties of these advanced material from the tensile results. For the PP composite filaments material case, the whiskers reinforcement increases Young's modulus and failure resistance, but it reduces the limit strength failure. For the PLA composites the addition of 1% wt of cellulose whiskers from the total volume fraction of the material, increase the Young’s modulus more than 50% and a decrease of the failure resistance and the limit strength of composite. The obtained composites fibers are very rigid and brittle. What follows, that the addition of cellulose whiskers micro fibers in PP matrix, provides mechanical properties more convenient compared to the PLA matrix.

scholarly journals Characterisation of the Material and Mechanical Properties of Atomic Force Microscope Cantilevers with a Plan-View Trapezoidal Geometry

2019 ◽  
Vol 9 (13) ◽  
pp. 2604 ◽  
Author(s):  
Ashley D. Slattery ◽  
Adam J. Blanch ◽  
Cameron J. Shearer ◽  
Andrew J. Stapleton ◽  
Renee V. Goreham ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Atomic Force Microscope ◽  
Young’S Modulus ◽  
Correction Factor ◽  
Young's Modulus ◽  
Spring Constant ◽  
Beam Equation ◽  
Euler Beam ◽  
Plan View ◽  
Atomic Force

Cantilever devices have found applications in numerous scientific fields and instruments, including the atomic force microscope (AFM), and as sensors to detect a wide range of chemical and biological species. The mechanical properties, in particular, the spring constant of these devices is crucial when quantifying adhesive forces, material properties of surfaces, and in determining deposited mass for sensing applications. A key component in the spring constant of a cantilever is the plan-view shape. In recent years, the trapezoidal plan-view shape has become available since it offers certain advantages to fast-scanning AFM and can improve sensor performance in fluid environments. Euler beam equations relating cantilever stiffness to the cantilever dimensions and Young’s modulus have been proven useful and are used extensively to model cantilever mechanical behaviour and calibrate the spring constant. In this work, we derive a simple correction factor to the Euler beam equation for a beam-shaped cantilever that is applicable to any cantilever with a trapezoidal plan-view shape. This correction factor is based upon previous analytical work and simplifies the application of the previous researchers formula. A correction factor to the spring constant of an AFM cantilever is also required to calculate the torque produced by the tip when it contacts the sample surface, which is also dependent on the plan-view shape. In this work, we also derive a simple expression for the torque for triangular plan-view shaped cantilevers and show that for the current generation of trapezoidal plan-view shaped AFM cantilevers, this will be a good approximation. We shall apply both these correction factors to determine Young’s modulus for a range of trapezoidal-shaped AFM cantilevers, which are specially designed for fast-scanning. These types of AFM probes are much smaller in size when compared to standard AFM probes. In the process of analysing the mechanical properties of these cantilevers, important insights are also gained into their spring constant calibration and dimensional factors that contribute to the variability in their spring constant.

Low-frequency viscoelastic properties of canine femoral artery in vivo

1979 ◽  
Vol 236 (5) ◽  
pp. H720-H724
Author(s):  
P. Sipkema
Keyword(s):  
Young’S Modulus ◽  
Femoral Artery ◽  
Constant Pressure ◽  
Young's Modulus ◽  
Low Frequency ◽  
Absolute Value ◽  
Average Value ◽  
Mean Pressure ◽  
Frequency Behavior

Mechanical properties of the canine femoral artery in vivo are measured as a function of frequency (0.0025--0.1 Hz) and as a function of mean pressure (10--16 kPa). Sinusoidal pressure variations are generated with a servo-controlled occluder system. The absolute value of the Young's modulus increases with mean pressure (E = 0.63 X 10(5) exp(0.211P)-N.m-2) at 0.05 Hz; where P is pressure. At heart rate frequencies (average value 2.22 Hz) this relation is: E = 1.25 X 10(5) exp(0.175P) N.m-2. The phase angle of the Young's modulus is independent of pressure at both frequencies. At 0.05 Hz we found: phi = 0.189 - 0.00788 P radians and at 2.22 Hz: phi = 0.0723 + 0.000428 P. The slope of both lines is not significantly different from zero slope (alpha = 0.05). Frequency dependence is studied at a constant pressure level (Pr, average value 14.3 kPa) just below the animals' mean pressure levels (average value 15.9 kPa). The frequency behavior of the elastic modulus is fitted with a function with two poles and two zeros (poles at 0.003 and 0.038 Hz; zeros at 0.0022 and 0.03 Hz).

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