Dynamic Responses of Plates With Viscoelastic Free Layer Damping Treatment

1996 ◽  
Vol 118 (3) ◽  
pp. 362-367 ◽  
Author(s):  
Sung Yi ◽  
M. Fouad Ahmad ◽  
H. H. Hilton
Keyword(s):  
Young’S Modulus ◽  
Layer Thickness ◽  
Young's Modulus ◽  
Dynamic Responses ◽  
Viscoelastic Damping ◽  
Free Layer ◽  
Modulus Ratio ◽  
Transient Responses ◽  
Damping Materials

Dynamic transient responses of plates with viscoelastic free damping layers are studied in order to evaluate free layer damping treatment performances. The effects of forcing frequencies and temperatures on free-layer viscoelastic damping treatment of plates are investigated analytically. Young’s modulus ratio of structures to viscoelastic damping materials and the damping layer thickness effects on the damping ability are also explored.

Dynamic Responses of Plates With Viscoelastic Damping Treatment

1993 ◽  
Author(s):  
Sung Yi ◽  
M. Fouad Ahmad ◽  
Harry H. Hilton
Keyword(s):  
Young’S Modulus ◽  
Layer Thickness ◽  
Young's Modulus ◽  
Dynamic Responses ◽  
Viscoelastic Damping ◽  
Free Layer ◽  
Modulus Ratio ◽  
Transient Responses ◽  
Damping Materials

Abstract Dynamic transient responses of plates with free damping layers are studied in order to evaluate free layer damping treatment performances. The effects of forcing frequencies and temperatures on free-layer viscoelastic damping treatment of plates are investigated analytically. Young’s modulus ratio of structures to viscoelastic damping materials and the damping layer thickness effects on the damping ability are also explored.

scholarly journals Evaluating Mechanical Properties of Thin Layers using Nanoindentation and Finite-Element Modeling: Implanted Metals and Deposited Layers

1996 ◽  
Vol 438 ◽  
Author(s):  
J. A. Knapp ◽  
D. M. Follstaedt ◽  
J. C. Barbour ◽  
S. M. Myers ◽  
J. W. Ager ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Finite Element ◽  
Finite Element Modeling ◽  
Yield Stress ◽  
Young’S Modulus ◽  
Layer Thickness ◽  
Young's Modulus ◽  
Thin Layers ◽  
Element Modeling ◽  
Surface Modified

AbstractWe present a methodology based on finite-element modeling of nanoindentation data to extract reliable and accurate mechanical properties from thin, hard films and surface-modified layers on softer substrates. The method deduces the yield stress, Young's modulus, and hardness from indentations as deep as 50% of the layer thickness.

scholarly journals Evaluation of the effectiveness of representative methods for determining Young's modulus and hardness from instrumented indentation data

2006 ◽  
Vol 21 (1) ◽  
pp. 225-233 ◽  
Author(s):  
Dejun Ma ◽  
Taihua Zhang ◽  
Chung Wo Ong
Keyword(s):  
Young’S Modulus ◽  
Young's Modulus ◽  
Maximum Error ◽  
Instrumented Indentation ◽  
Modulus Ratio ◽  
Material Parameters ◽  
Correction Scheme ◽  
Single Standard ◽  
Hardness Values ◽  
Hardening Coefficient

The effectiveness of Oliver & Pharr's (O&P's) method, Cheng & Cheng's (C&C’s) method, and a new method developed by our group for estimating Young's modulus and hardness based on instrumented indentation was evaluated for the case of yield stress to reduced Young's modulus ratio (σy/Er) ≥ 4.55 × 10−4 and hardening coefficient (n) ≤ 0.45. Dimensional theorem and finite element simulations were applied to produce reference results for this purpose. Both O&P's and C&C's methods overestimated the Young's modulus under some conditions, whereas the error can be controlled within ±16% if the formulation was modified with appropriate correction functions. Similar modification was not introduced to our method for determining Young's modulus, while the maximum error of results was around ±13%. The errors of hardness values obtained from all the three methods could be even larger and were irreducible with any correction scheme. It is therefore suggested that when hardness values of different materials are concerned, relative comparison of the data obtained from a single standard measurement technique would be more practically useful. It is noted that the ranges of error derived from the analysis could be different if different ranges of material parameters σy/Er and n are considered.

402 Hardness/Young's modulus ratio and tribology characteristics of hard thin film

2015 ◽  
Vol 2015.90 (0) ◽  
pp. 104-107
Author(s):  
Toshiyuki Saito ◽  
Miwa Hokii ◽  
Masahiro Suzuki
Keyword(s):  
Thin Film ◽  
Young’S Modulus ◽  
Young's Modulus ◽  
Modulus Ratio

scholarly journals Complex analysis of uniaxial compressive tests of the Mórágy granitic rock formation (Hungary)

2019 ◽  
Vol 41 (1) ◽  
pp. 21-32 ◽  
Author(s):  
M. Davarpanah ◽  
G. Somodi ◽  
L. Kovács ◽  
B. Vásárhelyi
Keyword(s):  
Young’S Modulus ◽  
Poisson’S Ratio ◽  
Granitic Rock ◽  
Young's Modulus ◽  
Intact Rock ◽  
Poisson's Ratio ◽  
Mechanical Parameters ◽  
Modulus Ratio ◽  
Rock Samples ◽  
Compressive Tests

AbstractUnderstanding the quality of intact rock is one of the most important parts of any engineering projects in the field of rock mechanics. The expression of correlations between the engineering properties of intact rock has always been the scope of experimental research, driven by the need to depict the actual behaviour of rock and to calculate most accurately the design parameters. To determine the behaviour of intact rock, the value of important mechanical parameters such as Young’s modulus (E), Poisson’s ratio (ν) and the strength of rock (σcd) was calculated. Recently, for modelling the behaviour of intact rock, the crack initiation stress (σci) is another important parameter, together with the strain (σ). The ratio of Young’s modulus and the strength of rock is the modulus ratio (MR), which can be used for calculations. These parameters are extensively used in rock engineering when the deformation of different structural elements of underground storage, caverns, tunnels or mining opening must be computed. The objective of this paper is to investigate the relationship between these parameters for Hungarian granitic rock samples. To achieve this goal, the modulus ratio (MR = E/σc) of 50 granitic rocks collected from Bátaapáti radioactive waste repository was examined. Fifty high-precision uniaxial compressive tests were conducted on strong (σc >100 MPa) rock samples, exhibiting the wide range of elastic modulus (E = 57.425–88.937 GPa), uniaxial compressive strength (σc = 133.34–213.04 MPa) and Poisson’s ratio (ν = 0.18–0.32). The observed value (MR = 326–597) and mean value of MR = 439.4 are compared with the results of similar previous researches. Moreover, the statistical analysis for all studied rocks was performed and the relationshipbetween MR and other mechanical parameters such as maximum axial strain $\left( {{\varepsilon }_{\text{a,}\,\text{max}}} \right)$for studied rocks was discussed.

scholarly journals Relation between Diffraction Young's Modulus Ratio and Elastic Anisotropy in Metals

2018 ◽  
Vol 67 (9) ◽  
pp. 855-860 ◽  
Author(s):  
Setsuo TAKAKI ◽  
Takuro MASUMURA ◽  
Fulin JIANG ◽  
Toshihiro TSUCHIYAMA
Keyword(s):  
Young’S Modulus ◽  
Elastic Anisotropy ◽  
Young's Modulus ◽  
Modulus Ratio

scholarly journals Vibration analysis of functionally graded materials for cylinder liner used in agricultural engine part

2019 ◽  
Vol 4 (1) ◽  
pp. 258-266
Author(s):  
Anand Prakash ◽  
Shiv Ranjan Kumar ◽  
Rahul Verma
Keyword(s):  
Boundary Conditions ◽  
Young’S Modulus ◽  
Vibration Analysis ◽  
Young's Modulus ◽  
Mass Density ◽  
Cylinder Liner ◽  
Functionally Graded ◽  
Power Exponent ◽  
Modulus Ratio ◽  
Engine Part

AbstractThe engine part is one of the major sources of vibration of agricultural machinery such as a tractor. Therefore, vibration analysis of agricultural engine part will improve the engine efficiency and agricultural performance. The main objective of present work was to study the dynamic behavior of functionally graded (FG) structural material for the application as cylinder liner as agricultural engine part. The vibration analysis of functionally graded (FG) beam was performed using Finite Element Method (FEM). A typical simply-supported FG beam was modeled in COMSOL Software, where the upper portion of the beam was alumina and the lower portion was steel. The basic properties of material such as Young’s Modulus and mass density were varied along the thickness according to the power law. The boundary conditions were also modeled, and parametric study was carried out with mass density and young’s modulus. Eigen value problem was solved and in turn natural frequency and mode shapes were obtained. The frequency ratio was calculated and compared for various boundary conditions. The finding of the results indicated that when power exponent was increased from 0 to 5, the nonlinear reduction in frequency was occurred but when power exponent was increased from 5 to 10, linear reduction in frequency was occurred. Also, the increase in power exponent caused the increase in frequency for Young’s Modulus ratio of 0.25 and 0.5, decrease in frequency for Young’s Modulus ratio of 2 and 4 and no change occurred for Young’s Modulus ratio of 1. The first non-dimensional frequency for Clamped-Clamped boundary condition was comparatively more than other boundary conditions and lowest frequency is obtained for Clamped –Free boundary conditions.

Optimization of fused deposition modeling process parameters using the Taguchi method to improve the tensile properties of 3D-printed polyether ether ketone

2021 ◽  
pp. 146442072110175
Author(s):  
Timoumi Mohamed ◽  
Najoua Barhoumi ◽  
Khalid Lamnawar ◽  
Abderrahim Maazouz ◽  
Amna Znaidi
Keyword(s):  
Tensile Properties ◽  
Young’S Modulus ◽  
Layer Thickness ◽  
Process Parameters ◽  
Fused Deposition Modeling ◽  
Young's Modulus ◽  
Fused Deposition ◽  
Polyether Ether Ketone ◽  
Deposition Modeling ◽  
Ether Ketone

The interesting mechanical properties of polyether ether ketone give the material a place among the foremost competitors when it comes to replacing metal. Fused deposition modeling has been recognized as an alternative method to process polyether ether ketone parts. In this study, the effect of different process parameters such as nozzle, bed, and radiant temperatures as well as printing speed and layer thickness on the tensile properties of three-dimensional printed polyether ether ketone was investigated. The optimization of the tensile properties of PEEK were studied by performing a reduced number of experiments, using the experimental design method based on the Taguchi approach which limits the number of experiments to 8 instead of 32. Results showed that a decent Young’s modulus was found by setting the nozzle temperature, print speed, and bed temperatures to their high levels and by setting the layer thickness and radiant temperature to their low level. Using these parameters, a Young’s modulus of 3.5 GPa was obtained, which represents 87.5% of the value indicated in the technical sheet. With these settings, we also found a tensile strength of 45.5 MPa, which corresponds to 46.4% of the value given by the studied polyether ether ketone material. A scanning electron microscopic investigation of the porosity and interlayer adhesion, confirmed that a higher bed temperature also tended to promote adhesion between layers.

The effect of confining pressure on elastic wave velocities and dynamic to static Young’s modulus ratio

Geophysics ◽  
2013 ◽  
Vol 78 (3) ◽  
pp. D135-D142 ◽  
Author(s):  
Mohammad Reza Asef ◽  
Ali Reza Najibi
Keyword(s):  
Young’S Modulus ◽  
Atmospheric Pressure ◽  
Critical Pressure ◽  
Young's Modulus ◽  
Confining Pressure ◽  
Least Square ◽  
Oil Well ◽  
Modulus Ratio ◽  
Wave Velocities ◽  
Static Young’S Modulus

We carried out laboratory experiments under dry conditions on limestone core specimens of Sarvak formation obtained from an oil well in the southwest of Iran. Our objective was to study the effect of confining pressure on the compressional and shear wave velocities ([Formula: see text], [Formula: see text]), and on the dynamic to static Young’s modulus ratio ([Formula: see text]). Furthermore, we made attempts to predict [Formula: see text] and [Formula: see text] at atmospheric pressure based on the same velocities at various confining pressures. These analyses revealed that, below a critical pressure with an increase in confinement [Formula: see text] and [Formula: see text] increased exponentially, representing a poroelastic regime. Above a critical pressure, however, the trend was linear. Likewise, we observed that with an increase in confinement, [Formula: see text] initially decreased exponentially, followed by a linear decreasing trend above the critical pressure. This indicated that [Formula: see text] is more responsive than [Formula: see text]. Accordingly, these observations infer that it is possible to predict [Formula: see text] based on [Formula: see text] at different confining stresses. This is an important improvement for geomechanical modeling of hydrocarbon and geothermal reservoirs because static parameters are more realistic input parameters. Besides, we derived the coefficients of the velocity-pressure equation for Sarvak limestone using least square regression analysis. More interestingly, we predicted [Formula: see text] and [Formula: see text] at atmospheric pressure based on these coefficients. Good agreement was observed between measured and predicted velocities at atmospheric pressure. Analysis of similar published experiments on oceanic basalts strongly confirmed these observations.

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