A Two-Parameter Function for Nanoscale Indentation Measurement of Near Surface Properties

2007 ◽  
Vol 130 (1) ◽  
Author(s):  
K. Farhang ◽  
L. E. Seitzman ◽  
B. Feng
Keyword(s):  
Young’S Modulus ◽  
Young's Modulus ◽  
Linear Functions ◽  
Accurate Estimation ◽  
Radius Of Curvature ◽  
Near Surface ◽  
Tip Radius ◽  
Parameter Function ◽  
Two Parameter ◽  
Indentation Measurement

A two-parameter function for estimation of projected area in instrumented indentation measurement is obtained to account for indenter tip imperfection. Imperfection near indenter tip is modeled using a spherical function and combined with a linear function describing the edge boundary of the indenter. Through an analytical fusion technique, the spherical and linear functions are combined into a single function with two unknown geometric parameters of tip radius of curvature and edge slope. Data from indentation measurement of force and displacement, using a Berkovich tip and single crystal alumina and silica samples, are implemented in the proposed area function yielding estimated values of Young’s modulus. Results were compared with that obtained from Oliver and Pharr technique for deep as well as shallow indentation regimes. The estimates for Young’s modulus were found to agree quite favorably. More importantly, in contrast to the Oliver–Pharr technique, the use of the two-parameter function resulted in a significantly more accurate estimation of Young’s modulus for shallow indentation depth of 0–50nm. The error in estimation of Young’s modulus was found to be within 10% for indentation depths of 25–50nm and within 20% for indentation depths of 0–25nm.

Near Surface Measurement of Mechanical Properties Using Instrumented Indentation Measurements

2005 ◽  
Author(s):  
K. Farhang ◽  
L. E. Seitzman ◽  
B. Feng
Keyword(s):  
Young’S Modulus ◽  
Young's Modulus ◽  
Surface Measurement ◽  
Accurate Estimation ◽  
Radius Of Curvature ◽  
Instrumented Indentation ◽  
Near Surface ◽  
Parameter Function ◽  
Two Parameter ◽  
Indentation Measurement

A two-parameter function for estimation of projected area in instrumented indentation measurement is obtained to account for indenter tip imperfection. Imperfection near indenter tip-end is modeled using a spherical function and combined with a linear function describing the edge boundary of the indenter. Through an analytical fusion technique the spherical and linear functions are combined into a single function with two unknown geometric parameters of tip radius of curvature and edge slope. Data from indentation measurement of force and displacement, using a Berkovich tip and single crystal alumina and silica samples, are implemented in the proposed area function yielding estimated values of Young’s modulus. Results were compared with that obtained from Oliver and Pharr technique for deep as well as shallow indentation regimes. The estimates for Young’s modulus were found to agree quite favorably. More importantly, in contrast to the Oliver-Pharr technique, the use of the two-parameter function resulted in a significantly more accurate estimation of Young’s modulus for shallow indentation depth of 0 to 100 nm. The error in estimation of Young’s modulus was found to be within 10 percent for indentation depths 25 nm to 50 nm and within 20 percent for indentation depths 0 to 25 nm.

Nano-Scale Indentation Measurement of Material Properties Using an Area Function of the Tip Geometry

2008 ◽  
Author(s):  
S. Ozcan ◽  
K. Farhang ◽  
P. Filip
Keyword(s):  
Modulus Of Elasticity ◽  
Fused Silica ◽  
Radius Of Curvature ◽  
Near Surface ◽  
Area Function ◽  
Atomic Force ◽  
Nanoindentation Measurement ◽  
Two Parameter ◽  
Indentation Measurement

A novel two-parameter area function for determination of near surface properties of Young’s modulus of elasticity and hardness has shown promise for compensating for the imperfection of the tip-end in an instrumented indentation measurement. This paper provides a comprehensive study involving a Berkovitch tip. The tip is utilized in an MTS nanoindentation measurement machine and used to establish load indentation information for fused silica samples. The geometry of the tip is then characterized independently using a highly accurate Atomic Force Microscope. Using the indentation data along with the two-parameter area function methodology, the tip-end radius of curvature is found to provide the most consistent value of modulus of elasticity. Independently, the data from the SEM measurement of the same tip is used to obtain the least squares estimation of the tip curvature. The two approaches yield favorable agreement in the estimation of tip-end radius of curvature. Therefore, the validity of the two-parameter area function method is proved. The method is shown to provide a robust, reliable and accurate measurement of modulus of elasticity and hardness in the nanoscale proximity of a surface.

The Site Tilt and Lander Transfer Function from the Short-Period Seismometer of InSight on Mars

2021 ◽  
Author(s):  
Alexander E. Stott ◽  
Constantinos Charalambous ◽  
Tristram J. Warren ◽  
William T. Pike ◽  
Robert Myhill ◽  
...  
Keyword(s):  
Young’S Modulus ◽  
Young's Modulus ◽  
Dust Devils ◽  
Total Change ◽  
Noise Sources ◽  
Element Analysis ◽  
Near Surface ◽  
Seismic Experiment ◽  
Short Period ◽  
Sensitivity Changes

ABSTRACT The National Aeronautics and Space Administration InSight mission has deployed the seismic experiment, SEIS, on the surface of Mars, and has recorded a variety of signals including marsquakes and dust devils. This work presents results on the tilt and local noise sources, which provide context to aid interpretation of the observed signals and allow an examination of the near-surface properties. Our analysis uses data recorded by the short-period sensors on the deck, throughout deployment and in the final configuration. We use thermal decorrelation to provide an estimate of the sol-to-sol tilt. This tilt is examined across deployment and over a Martian year. After each modification to the site, the tilt is seen to stabilize over 3–20 sols depending on the action, and the total change in tilt is <0.035°. Long-term tilt over a Martian year is limited to <0.007°. We also investigate the attenuation of lander-induced vibrations between the lander and SEIS. Robotic arm motions provide a known lander source in the 5–9 Hz bandwidth, yielding an amplitude attenuation of lander signals between 100 and 1000 times. The attenuation of wind sensitivity from the deck to ground presents a similar value in the 1.5–9 Hz range, thus favoring a noise dominated by lander vibrations induced by the wind. Wind sensitivities outside this bandwidth exhibit different sensitivity changes, indicating a change in the coupling. The results are interpreted through a finite-element analysis of the regolith with a depth-dependent Young’s modulus. We argue that discrepancies between this model and the observations are due to local compaction beneath the lander legs and/or anelasticity. An estimate for the effective Young’s modulus is obtained as 62–81 MPa, corroborating previous estimates for the top layer duricrust.

Calculation of the parameters of mechanical properties of the heart muscle

2020 ◽  
Vol 12 ◽  
pp. 42-52
Author(s):  
S. A. Muslov ◽  
◽  
A. I. Lotkov ◽  
S. D. Arutyunov ◽  
T. M. Albakova ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Young’S Modulus ◽  
Elastic Constants ◽  
Heart Muscle ◽  
Human Heart ◽  
Young's Modulus ◽  
Experimental Values ◽  
Two Parameter

A review of studies of the mechanical properties of human and animal heart tissues has been performed. Based on literature data, a form of approximating function is found for the dependence of the Young’s modulus of the ventricles of the human heart on the magnitude of the deformation. The average values of the Young’s modulus and other elastic constants were calculated and compared with the known experimental values. The coefficients C1 and C2 of the two-parameter hyperelastic myocardial Mooney-Rivlin model are calculated.

scholarly journals PPV Criterion of a Rock Slope Imbedded with a Fault subjected to Blasting P-Waves

2020 ◽  
Vol 2020 ◽  
pp. 1-7
Author(s):  
Shiwei Lu ◽  
Chuanbo Zhou ◽  
Zhen Zhang ◽  
Ling Ji ◽  
Nan Jiang
Keyword(s):  
Slope Stability ◽  
Young’S Modulus ◽  
Poisson’S Ratio ◽  
Rock Slope ◽  
Young's Modulus ◽  
Intact Rock ◽  
P Wave ◽  
Poisson's Ratio ◽  
Rock Slopes ◽  
Near Surface

The open-pit mining slopes continue to become higher and steeper with the continuous exploitation of near-surface mineral resources. The blasting excavation exerts a significance influence on the slope stability. In fact, intact rock slopes do not exist and slope stability is controlled by the geological defects. In this paper, the stability of a rock slope imbedded with a fault is considered. The P-wave component of blasting seismic waves is focused on and the fault is simplified as a semi-infinite crack. In background of Daye iron mine, the peak particle velocity (PPV) threshold is determined based on the linear elastic fracture dynamics. The influence of frequency, Young's modulus, and Poisson's ratio is studied to modify the PPV threshold. Results show that (1) the PPV threshold decreases with the increasing Young's modulus and Poisson's ratio, but increases with the increasing frequency; (2) the initiation angle is immune to Young's modulus and the frequency, and only depends on the Poisson's ratio; (3) the PPV criterion is finally determined as 1.47 cm/s when the frequency f ≤ 10 Hz, 1.47 cm/s–3.30 cm/s when 10 Hz < f ≤ 50 Hz and 3.37 cm/s–6.59 cm/s when f > 50 Hz, which are far less than that of intact rock slopes; (4) The north slope is quite safe if the proposed PPV threshold is not violated due to the variation range of the initiation angle θ0.

Analytical Modeling of Top Roller Position for Multiple Pass (3-Roller) Cylindrical Forming of Plates

2006 ◽  
Author(s):  
A. H. Gandhi ◽  
H. K. Raval
Keyword(s):  
Young’S Modulus ◽  
Analytical Model ◽  
Young's Modulus ◽  
Material Behavior ◽  
Analytical Models ◽  
Radius Of Curvature ◽  
Single Pass ◽  
Multiple Pass ◽  
Efficient Performance ◽  
Constant E

As forming of the double or multiple curvature surfaces, includes roller forming at least once in the sequential process; its efficient performance is of great importance for controlling the final product dimensions. Most efficient and economical way to produce the cylinder is to roll the plate through the roller in single pass. Literature review revels that, most of the reported analytical models for the prediction of springback were developed with the assumption of zero initial strain. However, in practice multiple pass bending is recommended to work within the power limitation of the machine and to improve the accuracy of the final product. An attempt is made to develop the analytical model for estimation of top roller position as a function of desired radius of curvature, for multiple pass 3-roller forming of cylinders, considering real material behavior. Due to the change of Young's modulus of elasticity (E) under deformation, the springback is larger than the springback calculated with constant E. Developed analytical model was modified to include the effect of change of Young's modulus during the deformation. Developed multiple pass analytical models were compared with the single pass analytical model and experiments (on pyramid type 3-roller bending machine).

Assessment and Verification of a Novel Method for Near Surface Measurement of Mechanical Properties

2007 ◽  
Vol 129 (2) ◽  
pp. 314-320 ◽  
Author(s):  
S. Ozcan ◽  
K. Farhang ◽  
P. Filip
Keyword(s):  
Modulus Of Elasticity ◽  
Fused Silica ◽  
Surface Measurement ◽  
Radius Of Curvature ◽  
Near Surface ◽  
Area Function ◽  
Atomic Force ◽  
Scanning Electron Microscope Measurement ◽  
Nanoindentation Measurement ◽  
Two Parameter

A novel two-parameter area function for determination of near surface properties of Young’s modulus of elasticity and hardness has shown promise for compensating for the imperfection of the tip-end in an instrumented indentation measurement. This paper provides a comprehensive study involving a Berkovitch tip. The tip is utilized in an MTS nanoindentation measurement machine and is used to establish load indentation information for fused silica samples. The geometry of the tip is then characterized independently using a highly accurate atomic force microscope. Using the indentation data along with the two-parameter area function methodology, the tip-end radius of curvature is found to provide the most consistent value of modulus of elasticity. Independently, the data from the scanning electron microscope measurement of the same tip is used to obtain the least-squares estimation of the tip curvature. The two approaches yield favorable agreement in the estimation of tip-end radius of curvature. Therefore, the validity of the two-parameter area function method is proved. The method is shown to provide a robust, reliable, and accurate measurement of modulus of elasticity and hardness in the nanoscale proximity of a surface.

Effect of Sample Materials on the AFM Tip-Based Dynamic Ploughing Process

2011 ◽  
Vol 314-316 ◽  
pp. 492-496
Author(s):  
Yong Da Yan ◽  
Wei Tao Liu ◽  
Zhen Jiang Hu ◽  
Xue Sen Zhao ◽  
Jiu Chun Yan
Keyword(s):  
Young’S Modulus ◽  
Young's Modulus ◽  
Sample Surface ◽  
Machining Process ◽  
Oscillator Model ◽  
Tapping Mode ◽  
Tip Radius ◽  
Spring Constants

To study the effect of different sample materials on the nano dynamic ploughing process in the AFM tapping mode, the spring-oscillator model is employed to simulate the vibrating AFM tip to deform the sample surface. On the surface of different samples with the Young’s modulus of 0.2 GPa, 80 GPa and 180 Gpa, the interaction between the tip and the sample is simulated with different driven amplitudes, spring constants, tip radius and original tip-sample distances. These effects are studied. Results show that the sample with a smaller Young’s modulus is suitable for being used as the sample machined by the dynamic ploughing technique. When the Young’s modulus is greater than 80 GPa, the machine depth is so small that the machining process can not be controlled as we required.

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