Distribution of internal stresses and stored energy density within a grain of deformed polycrystal

The evolution of stored energy and associated thermal behaviour was investigated for an ultrafine grained Ti-IF steel severely deformed by Equal Channel Angular Pressing (ECAP) followed by cold rolling at ambient and liquid nitrogen temperatures. Bulk stored energy measurements by Differential Scanning Calorimetry (DSC) returned 350-600 whereas local stored energy estimates from microhardness, Electron Back-Scattering Diffraction (EBSD) and X-ray line profile analysis resulted in 5-140 . Higher bulk stored energy values correspond to the enthalpy release from all sources of strain in the material volume as well as Ti precipitation during annealing while the lower local stored energy range alludes only to dislocation content or internal stresses. An apparent activation energy of 500-550 suggests sluggish recrystallisation due to excess of Ti in solid solution.

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Relationship between the stored energy density and intensity

The Journal of the Acoustical Society of America ◽

10.1121/1.2025851 ◽

1988 ◽

Vol 84 (S1) ◽

pp. S148-S148

Author(s):

G. Maidanik ◽

J. Dickey

Keyword(s):

Energy Density ◽

Stored Energy

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Function-refresh algorithms for determining the stored energy density of nonlinear elastic orthotropic materials directly from experimental data

International Journal of Non-Linear Mechanics ◽

10.1016/j.ijnonlinmec.2018.09.011 ◽

2018 ◽

Vol 107 ◽

pp. 16-33 ◽

Cited By ~ 5

Author(s):

José Crespo ◽

Francisco J. Montáns

Keyword(s):

Experimental Data ◽

Energy Density ◽

Orthotropic Materials ◽

Stored Energy ◽

Nonlinear Elastic

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Simulation of a Layered Resonator for a Microfluidic Ultrasonic Separator

ASME 4th International Conference on Nanochannels, Microchannels, and Minichannels, Parts A and B ◽

10.1115/icnmm2006-96247 ◽

2006 ◽

Author(s):

Yijun Shen ◽

Mark A. Atherton

Keyword(s):

Energy Density ◽

Pressure Distribution ◽

Standing Wave ◽

Acoustic Pressure ◽

Separation Performance ◽

Experimental Measurements ◽

Driving Frequency ◽

Stored Energy ◽

Acoustic Characteristics ◽

Small Spherical Particle

This paper focuses on the simulation of a layered resonator for a microfluidic ultrasonic separator with a special emphasis on analysing the stored energy-frequency product in the microfluid chamber. Since the acoustic force acting on a small spherical particle in a standing wave in the cavity of an ultrasonic separator is proportional to the product of the energy density in the standing wave and the driving frequency, the energy-frequency product can be used as a prediction of the separation performance in an ultrasonic separator. The electro-acoustic characteristics of the resonator under different conditions are also investigated. In particular, the influence of the reflector thickness on the stored energy-frequency product of the layered resonator is examined. Furthermore, the acoustic pressure distribution in the fluid chamber of the ultrasonic separator is investigated in detail. Predicted results from simulations compare well with experimental measurements and show that the model can be used to predict the electro-acoustic characteristics and the separation performance.

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Achieving high discharge energy density and efficiency with NBT-based ceramics for application in capacitors

Journal of Materials Chemistry C ◽

10.1039/c9tc00087a ◽

2019 ◽

Vol 7 (14) ◽

pp. 4072-4078 ◽

Cited By ~ 82

Author(s):

Zhongbin Pan ◽

Di Hu ◽

Yang Zhang ◽

Jinjun Liu ◽

Bo Shen ◽

...

Keyword(s):

Energy Storage ◽

Energy Density ◽

High Efficiency ◽

Energy Storage Density ◽

Discharge Energy ◽

Stored Energy ◽

High Discharge ◽

Storage Density ◽

Recoverable Energy ◽

Discharge Energy Density

The 0.94(BNT–BST)–0.06KNN ceramic possesses an excellent stored energy storage density (Ws = ∼3.13 J cm−3), a recoverable energy storage density (Wr = ∼2.65 J cm−3), and maintains a relatively high efficiency (η ∼ 84.6%).

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A Quantitative Test for Ozone Resistance of Rubber Vulcanizates

Rubber Chemistry and Technology ◽

10.5254/1.3540471 ◽

1974 ◽

Vol 47 (4) ◽

pp. 895-905 ◽

Cited By ~ 6

Author(s):

Z. W. Wilchinsky ◽

E. N. Kresge

Keyword(s):

Elastic Modulus ◽

Energy Density ◽

Critical Stress ◽

Critical Strain ◽

Tensile Force ◽

Critical Value ◽

Stored Energy ◽

Simplified Procedure ◽

Continuous Range ◽

Ozone Resistance

Abstract A simplified procedure was developed for evaluating ozone resistance of rubber vulcanizates in terms of critical stress—strain and stored energy density parameters. A selected tensile force of appropriate magnitude is applied to a tapered specimen to produce a continuous range of stress. While thus stretched, the specimen is conditioned for 16 h, then exposed to ozone for 24 h. In the portion of the specimen where the stress is greater than a critical value σc, ozone cracking occurs, whereas in the portion of the specimen where the stress is less than σc there are no cracks. Values of σc the critical strain εc, the critical elastic stored energy Wc, and the elastic modulus E are determined from the position of the boundary between the cracked and uncracked zones, the average elongation of the stressed specimen, and the specimen geometry. The quantity Wc was found suitable for quantitatively characterizing ozone resistance by a single parameter.

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Reinforcement of Natural Rubber with Silanized Precipitated Silica Nanofiller

Rubber Chemistry and Technology ◽

10.5254/1.3547914 ◽

2005 ◽

Vol 78 (5) ◽

pp. 793-805 ◽

Cited By ~ 5

Author(s):

A. Ansarifar ◽

N. Ibrahim ◽

M. Bennett

Keyword(s):

Mechanical Properties ◽

Tensile Strength ◽

Zinc Oxide ◽

Reaction Mechanism ◽

Energy Density ◽

Natural Rubber ◽

Elemental Sulfur ◽

Stored Energy ◽

Tear Strength ◽

Precipitated Silica

Abstract The effect of a large amount of precipitated amorphous white silica nanofiller, pre-treated with bis[3-triethoxysilylpropyl-)tetrasulfide (TESPT), on the mechanical properties of a sulfur-cured natural rubber (NR) was studied. TESPT chemically adheres silica to rubber and also prevents silica from interfering with the reaction mechanism of sulfur-cure. The silica particles were fully dispersed in the rubber, which was cured primarily by using sulfur in TESPT, or, by adding a small amount of elemental sulfur to the cure system. The cure was also optimized by incorporating sulphenamide accelerator and zinc oxide into the rubber. The hardness, tear strength, tensile strength, and stored energy density at break of the vulcanizate were substantially improved when the filler was added. Interestingly, these properties were also enhanced when the rubber was cured primarily by using sulfur in TESPT.

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