Young’s modulus of peritubular and intertubular human dentin by nano-indentation tests

Abstract Thermo-mechanical reliability assessment for sintered silver is a crucial issue as sintered silver is a promising candidate of die-attachment materials for power devices. In this paper, the nano-indentation tests are performed for sintered silver in typical die-attach interconnection under different thermal cycles. Based on thermal cycling test, the Young's modulus and hardness of sintered silver layer have been presented. It is found that the Young's modulus and hardness of sintered silver layer changes slightly although the microstructure of sintered silver also presents some variations. The stress and strain curves for different thermal cycling tests for sintered silver based on reverse analysis of nano-indentation are also given. The results show that the elastoplastic constitutive equations change significantly after thermal cycling tests, and the yielding stress decreases remarkably after 70 thermal cycles. The experimental investigation also show that the cracking behaviors of sintered silver depends on its geometry characteristics, which implies that the possible optimization of sintered silver layer could enhance its thermo-mechanical performance.

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Evaluation of Mechanical Properties of SOFC Components by Nano-Indentation Tests

ASME 2010 8th International Fuel Cell Science, Engineering and Technology Conference: Volume 2 ◽

10.1115/fuelcell2010-33158 ◽

2010 ◽

Author(s):

Hideaki Ito ◽

Kazuhisa Sato ◽

Atsushi Unemoto ◽

Koji Amezawa ◽

Tatsuya Kawada

Keyword(s):

Mechanical Properties ◽

Young’S Modulus ◽

Crystal Orientation ◽

Young's Modulus ◽

Yttria Stabilized Zirconia ◽

Stabilized Zirconia ◽

Indentation Method ◽

Nano Indentation ◽

Electron Backscattering Diffraction ◽

Indentation Tests

The Young’s modulus and the hardness of single crystals and polycrystalline sintered compacts of yttria-stabilized zirconia (YSZ), (Y2O3)x(ZrO2)1−x (x = 0.08, 0.10) was investigated by using the nano-indentation method. Together with results obtained by the secondary electron microscope observation and the electron backscattering diffraction analysis, the effect of the crystal orientation on the mechanical properties was discussed. It was empirically demonstrated that the Young’s modulus of YSZ depends on the crystal orientation. The Young’s modulus of YSZ showed the highest value on the (001) surface while the lowest value on the (111) surface. However, the observed anisotropy of the Young’s modulus was rather small compared with predicted one from the single crystal elastic constants in literature. Compared with the Young’s modulus, the anisotropy of the hardness of YSZ was less significant.

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Measurement of Young's Modulus and Poisson's Ratio of Thin Film by Combination of Bulge Test and Nano-Indentation

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.33-37.969 ◽

2008 ◽

Vol 33-37 ◽

pp. 969-974 ◽

Cited By ~ 1

Author(s):

Bong Bu Jung ◽

Seong Hyun Ko ◽

Hun Kee Lee ◽

Hyun Chul Park

Keyword(s):

Thin Film ◽

Mechanical Properties ◽

Young’S Modulus ◽

Poisson’S Ratio ◽

Young's Modulus ◽

Applied Pressure ◽

Indentation Test ◽

Poisson's Ratio ◽

Bulge Test ◽

Nano Indentation

This paper will discuss two different techniques to measure mechanical properties of thin film, bulge test and nano-indentation test. In the bulge test, uniform pressure applies to one side of thin film. Measurement of the membrane deflection as a function of the applied pressure allows one to determine the mechanical properties such as the elastic modulus and the residual stress. Nano-indentation measurements are accomplished by pushing the indenter tip into a sample and then withdrawing it, recording the force required as a function of position. . In this study, modified King’s model can be used to estimate the mechanical properties of the thin film in order to avoid the effect of substrates. Both techniques can be used to determine Young’s modulus or Poisson’s ratio, but in both cases knowledge of the other variables is needed. However, the mathematical relationship between the modulus and Poisson's ratio is different for the two experimental techniques. Hence, achieving agreement between the techniques means that the modulus and Poisson’s ratio and Young’s modulus of thin films can be determined with no a priori knowledge of either.

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Elastic constants of inflated lobes of dog lungs

Journal of Applied Physiology ◽

10.1152/jappl.1976.40.4.508 ◽

1976 ◽

Vol 40 (4) ◽

pp. 508-513 ◽

Cited By ~ 89

Author(s):

S. J. Lai-Fook ◽

T. A. Wilson ◽

R. E. Hyatt ◽

J. R. Rodarte

Keyword(s):

Bulk Modulus ◽

Young’S Modulus ◽

Elastic Constants ◽

Young's Modulus ◽

Poisson Ratio ◽

Inflation Pressure ◽

Initial State ◽

Volume Curve ◽

Pressure Volume Curve ◽

Indentation Tests

The elastic constants of dog lungs were determined at various degrees of inflation. In one set of experiments, the lobes were subjected to deformations that approximated the conditions of uniaxial loading. These data, together with the bulk modulus data obtained from the local slope of the pressure-volume curve, were used to determine the two elastic moduli that are needed to describe small nonuniform deformations about an initial state of uniform inflation. The bulk modulus was approximately 4 times the inflation pressure, and Young's modulus was approximately 1.5 times the inflation pressure. In a second set of experiments, lobes were subjected to indentation tests using cylindric punches 1–3 cm in diameter. The value for Young's modulus obtained from these data was slightly higher, approximately twice the inflation pressure. These experiments indicate that the lung is much more easily deformable in shear than in dilatation and that the Poisson ratio for the lung is high, approximately 0.43.

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Evaluation of WB Coatings by Scanned Imaging Microscopy

Ultrasonic Nondestructive Evaluation for Material Science and Industries ◽

10.1115/pvp2003-1861 ◽

2003 ◽

Author(s):

Jikai Du ◽

Bernhard R. Tittmann

Keyword(s):

Young’S Modulus ◽

Young's Modulus ◽

Attenuation Coefficients ◽

High Attenuation ◽

Nano Indentation ◽

Atomic Force ◽

Acoustic Evaluation ◽

Acoustic Velocities ◽

Thick Coatings ◽

Scanning Acoustic Microscope

Organic thick coatings (epoxy, polyurethane, and acrylic-urethane) have been widely applied to high modulus substrates (e.g., steel) for anticorrosion protection. To improve performance, reinforced components (clay, bochmite, nanopaticles, etc.) are usually added to these coatings. However, the acoustic evaluation of these coatings is difficult due to their low acoustic velocities and high attenuation coefficients. In this paper, first, the scanning acoustic microscope (SAM) is used to image sub-surfaces, coating/substrate interfaces, and to measure acoustic velocities. Different phases can be observed on some coatings and defects can be found at some interfaces. Secondly, the atomic force microscope (AFM) is applied to image surfaces at high resolution (compared to SAM). These results agree with SAM images. Thirdly, a nano-indentation technique is utilized to measure the reduced Young’s modulus and absolute hardness of the coatings. The results show that epoxy has the highest Young’s modulus and acrylic-urethane has the lowest. Reinforced components can either increase or decrease Young’s modulus, and hardness depending on the coating material. Finally, results from the SAM, AFM and nano-indentation are compared and analyzed to optimize the evaluation.

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Impact of Adhesive Application and Moisture on the Mechanical Properties of the Adhesive Interface Determined by the Nano-indentation Technique

Operative Dentistry ◽

10.2341/08-36 ◽

2009 ◽

Vol 34 (1) ◽

pp. 51-57 ◽

Cited By ~ 8

Author(s):

C. Higashi ◽

M. D. Michel ◽

A. Reis ◽

A. D. Loguercio ◽

O. M. M. Gomes ◽

...

Keyword(s):

Mechanical Properties ◽

Young’S Modulus ◽

Young's Modulus ◽

Adhesive Layer ◽

Single Bond ◽

Hybrid Layer ◽

Nano Indentation ◽

Water Based ◽

Adhesive Application ◽

Demineralized Dentin

Clinical Relevance The vigorous rubbing action of acetone and ethanol/water-based adhesives into dry demineralized dentin resulted in high nanohardness and Young's modulus in the hybrid layer, and moisture increased the nanohardness and Young's modulus of Adper Single Bond Plus in the adhesive layer.

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