Investigation of the relationship between work done during indentation and the hardness and Young's modulus obtained by indentation testing

2008 ◽  
Vol 99 (8) ◽  
pp. 852-857 ◽  
Author(s):  
J. Chen ◽  
S. J. Bull
Keyword(s):  
Young’S Modulus ◽  
Young's Modulus ◽  
Indentation Testing ◽  
Work Done ◽  
The Relationship

Is it necessary to calculate Young’s modulus in AFM nanoindentation experiments regarding biological samples?

2020 ◽  
Vol 12 ◽  
Author(s):  
S.V. Kontomaris ◽  
A. Malamou ◽  
A. Stylianou
Keyword(s):  
Young’S Modulus ◽  
Biological Samples ◽  
Young's Modulus ◽  
Reference Sample ◽  
Nonlinear Behavior ◽  
Accurate Method ◽  
Accurate Solution ◽  
Hertz Model ◽  
Work Done

Background: The determination of the mechanical properties of biological samples using Atomic Force Microscopy (AFM) at the nanoscale is usually performed using basic models arising from the contact mechanics theory. In particular, the Hertz model is the most frequently used theoretical tool for data processing. However, the Hertz model requires several assumptions such as homogeneous and isotropic samples and indenters with perfectly spherical or conical shapes. As it is widely known, none of these requirements are 100 % fulfilled for the case of indentation experiments at the nanoscale. As a result, significant errors arise in the Young’s modulus calculation. At the same time, an analytical model that could account complexities of soft biomaterials, such as nonlinear behavior, anisotropy, and heterogeneity, may be far-reaching. In addition, this hypothetical model would be ‘too difficult’ to be applied in real clinical activities since it would require very heavy workload and highly specialized personnel. Objective: In this paper a simple solution is provided to the aforementioned dead-end. A new approach is introduced in order to provide a simple and accurate method for the mechanical characterization at the nanoscale. Method: The ratio of the work done by the indenter on the sample of interest to the work done by the indenter on a reference sample is introduced as a new physical quantity that does not require homogeneous, isotropic samples or perfect indenters. Results: The proposed approach, not only provides an accurate solution from a physical perspective but also a simpler solution which does not require activities such as the determination of the cantilever’s spring constant and the dimensions of the AFM tip. Conclusion: The proposed, by this opinion paper, solution aims to provide a significant opportunity to overcome the existing limitations provided by Hertzian mechanics and apply AFM techniques in real clinical activities.

Transverse Young's Moduli and Cell Shapes in Coniferous Early Wood

Holzforschung ◽  
2002 ◽  
Vol 56 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Ugai Watanabe ◽  
Minoru Fujita ◽  
Misato Norimoto
Keyword(s):  
Young’S Modulus ◽  
Young's Modulus ◽  
Bending Moment ◽  
Cell Models ◽  
Young’S Moduli ◽  
Cell Shapes ◽  
The Difference ◽  
Square Cells ◽  
Experimental Values ◽  
The Relationship

Summary The relationship between transverse Young's moduli and cell shapes in coniferous early wood was investigated using cell models constructed by two dimensional power spectrum analysis. The calculated values of tangential Young's modulus qualitatively explained the relationship between experimental values and density as well as the difference in experimental values among species. The calculated values of radial Young's modulus for the species having hexagonal cells agreed well with the experimental values, whereas, for the species having square cells, the calculated values were much larger than the experimental values. This result was ascribed to the fact that the bending moment on the radial cell wall of square cell models was calculated to be small. It is suggested that the asymmetrical shape of real wood cells or the behavior of nodes during ell deformation is an important factor in the mechanism of linear elastic deformation of wood cells.

Prediction of Springback in Metal Forming of Diaphragm of Automotive Horn Based on BPANN

2010 ◽  
Vol 139-141 ◽  
pp. 594-599
Author(s):  
Yan Qiu Zhang ◽  
Shu Yong Jiang ◽  
Yu Feng Zheng
Keyword(s):  
Young’S Modulus ◽  
Metal Forming ◽  
Young's Modulus ◽  
Steel Strip ◽  
Back Propagation ◽  
Spring Steel ◽  
Yield Ratio ◽  
Punch Radius ◽  
Cold Rolled ◽  
The Relationship

The spring steel strip 50CrVA which is cold rolled was applied to manufacture the diaphragm of the automotive horn by means of sheet metal forming. The combination of the experiments with back-propagation artificial neural network (BPANN) is used to solve the springback problem of the diaphragm. Experiments have shown that a 4-8-1 BPANN is able to predict the springback of the diaphragm successfully, and the network is able to model the relationship between the springback of the diaphragm and the process parameters rationally. BPANN simulation results and experimental ones have shown that the springback of the diaphragm is particularly influenced by such parameters as blank thickness, Young’s modulus, punch radius and yield ratio. Furthermore, the springback of the diaphragm decreases with the increase of blank thickness and Young’s modulus, but increases with the increase of punch radius and yield ratio.

Modified Model for Static Behavior of Microcantilever Gas Sensor Adsorbed with Monolayer Molecules

2011 ◽  
Vol 415-417 ◽  
pp. 455-459
Author(s):  
Xiao Ming Wang ◽  
Fei Wang ◽  
Xue Zeng Zhao ◽  
Da Lei Jing
Keyword(s):  
Young’S Modulus ◽  
Young's Modulus ◽  
Curvature Radius ◽  
Static Behavior ◽  
Neutral Layer ◽  
Modified Model ◽  
Adsorbed Molecules ◽  
Microcantilever Sensors ◽  
The Relationship ◽  
Layer Position

The modified static bending model of microcantilever with monolayer molecules has been established based on energy method, in which the change in neutral layer position caused by adsorption-induced stress has been considered. On this basis, we have analyzed the relationship between the bending curvature radius of a microcantilever with its thickness, Young’s modulus and molecule-molecule distance of adsorbed molecules when it is adsorbed with monolayer water molecules. Additionally, we have investigated the effect of change in neutral layer position on the static behavior of microcantilever sensors and have found that: 1) the bending curvature radius of microcantilever is affected by its Young’s modulus, thickness and distance of adsorbed molecules respectively; 2)the predicted error of bending curvature radius caused by the change in neutral layer position slightly increases with decreasing Young’s modulus and thickness, whereas the effect of distance between adsorbed molecules on the error is significant.

Effect of the Quenching Temperature on the Phase Composition and Youngʹs Modulus of Corrosion-Resistant and Biocompatible Titanium Alloys

2019 ◽  
Vol 946 ◽  
pp. 309-314 ◽  
Author(s):  
Anatoly G. Illarionov ◽  
S.V. Grib ◽  
A.V. Huppeev
Keyword(s):  
Phase Composition ◽  
Titanium Alloys ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Two Phase ◽  
Quenching Temperature ◽  
Thermo Calc Software ◽  
Extreme Change ◽  
The Relationship ◽  
Micro Indentation

The relationship between the phase composition and the Young’s modulus in quenched PT-7M, Ti-6Al-7Nb, BT16 titanium alloys has been studied using the structural analysis, thermodynamic calculations in the Thermo-Calc software and micro-indentation. It is found that the nature of the change in the Young’s modulus in the investigated titanium alloys after quenching from the two-phase α+β-region depends on the chemical composition of the alloy, which determines the nature of the observed metastable phases (α', α", ω, β). The correlation between the extreme change in the Young’s modulus from the quenching temperature and the so-called interatomic bonding force (Fb) calculated from the electronic structure parameters of the α, α', β phases was shown for the Ti-6Al-7Nb alloy. The relationship between the limits of the Young’s modulus of the investigated alloys during quenching with the level of their alloying with α-and β-stabilizers is shown.

scholarly journals The relationship between the Young’s modulus and dry etching rate of polydimethylsiloxane (PDMS)

2019 ◽  
Vol 21 (1) ◽  
Author(s):  
Matthew L. Fitzgerald ◽  
Sara Tsai ◽  
Leon M. Bellan ◽  
Rebecca Sappington ◽  
Yaqiong Xu ◽  
...  
Keyword(s):  
Young’S Modulus ◽  
Young's Modulus ◽  
Etching Rate ◽  
Dry Etching ◽  
The Relationship

Correlations among Physical and Mechanical Parameters of Rocks

2017 ◽  
Vol 865 ◽  
pp. 366-372
Author(s):  
Jing Sen Liu ◽  
Hai Bo Li ◽  
Guo Kai Zhang ◽  
Jian Deng
Keyword(s):  
Shear Modulus ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
P Wave ◽  
Physical Parameters ◽  
Dynamic Shear Modulus ◽  
Regression Equations ◽  
Mechanical Parameters ◽  
P Wave Velocity ◽  
The Relationship

In order to improve the accuracy of the rock mechanical parameters, the correlations among physical and mechanical parameters were investigated. A large number of laboratory testing results curried out on 408 rock specimens including metamorphic rocks, sedimentary rocks and igneous rocks. Through the statistical analysis of the laboratory test data, several regression equations among rock material parameters were established. The research suggests that, in addition to Poisson's ratio, the mechanical parameters (unconfined compressive strength (UCS), elastic Young’s modulus, shear modulus) relate well to physical parameters (porosity, P-wave velocity), and the relationships are mainly described by power and exponential correlations which have good squared regression coefficients. The correlation between elastic Young’s modulus and dynamic elastic modulus was established, as well as the relationship between shear modulus and dynamic shear modulus.

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