Shear strength measurements and hydrostatic compression of rhenium diboride under high pressures

The structural, electronic, and absorption properties of crystalline 3,3′-dinitroamino-4,4′-azoxyfurazan (DNOAAF), 3,3′-dinitro-4,4′-azoxyfurazan (DNOAF), and 3,4-bis(3-nitrofurazan-4-yl)furoxan (BNTF) under hydrostatic compression of 0–190 GPa have been comparatively studied using density functional theory with dispersion corrections. Their crystal structures were relaxed using three types of vdW corrections such as the PBE-G06, PBE-TS, and PW91-OBS functionals at ambient conditions. The results indicate that PBE-G06 is the best functional for studying them. The compression ratios show that DNOAAF is stiffer than the other two at high pressures. An analysis of the band gaps and density of states indicates that they become more and more sensitive under compression. In the range of 0–120 GPa, BNTF is the most unstable. However, in the range of 120–190 GPa, DNOAF becomes the more unstable. The three crystals have higher optical activity at high pressures, and moreover, applied pressures change their optical adsorption activity order.

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Shear Strength of Titanium Diboride under Shock Wave and Static Compressions

Materials Science Forum ◽

10.4028/www.scientific.net/msf.638-642.1023 ◽

2010 ◽

Vol 638-642 ◽

pp. 1023-1028 ◽

Cited By ~ 1

Author(s):

Dattatraya P. Dandekar

Keyword(s):

Mechanical Properties ◽

Shock Wave ◽

Shear Strength ◽

Titanium Diboride ◽

High Pressures ◽

Recent Measurement ◽

Plane Shock ◽

Wave Compression ◽

High Pressures And Temperatures ◽

Shock Wave Compression

The mechanical behavior of ceramics under high pressures and temperatures is a subject of considerable interest. Since high pressures can be generated under static or dynamic conditions, it is necessary to measure mechanical properties of the materials under both. In the present work, compression and shear strength of titanium diboride measured under plane shock wave compression is revealingly compared with the recent measurement of compression and shear strength of titanium diboride obtained under static high pressures.

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Ion tracks in apatite at high pressures: the effect of crystallographic track orientation on the elastic properties of fluorapatite under hydrostatic compression

Physics and Chemistry of Minerals ◽

10.1007/s00269-009-0340-0 ◽

2009 ◽

Vol 37 (6) ◽

pp. 371-387 ◽

Cited By ~ 9

Author(s):

Pascal Schouwink ◽

Ronald Miletich ◽

Angela Ullrich ◽

Ulrich A. Glasmacher ◽

Christina Trautmann ◽

...

Keyword(s):

Elastic Properties ◽

High Pressures ◽

Hydrostatic Compression ◽

Ion Tracks

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High-pressure compressibility and shear strength data for soils

Canadian Geotechnical Journal ◽

10.1139/cgj-2018-0235 ◽

2019 ◽

Vol 56 (7) ◽

pp. 1042-1048 ◽

Cited By ~ 1

Author(s):

A.D. Barr ◽

S.D. Clarke ◽

M. Petkovski

Keyword(s):

High Pressure ◽

Shear Strength ◽

High Pressures ◽

Triaxial Compression ◽

Failure Surface ◽

Low Pressure ◽

Strength Data ◽

Buried Explosive ◽

Explosive Devices ◽

Soil Behaviour

Soil behaviour is often an important consideration in the design of protective systems for blast and impact threats, as the properties of a soil can greatly affect the impulse generated from buried explosive devices, or the ability of a soil-filled structure to resist ballistic threats. Numerical modelling of these events often relies on extrapolation from low-pressure experiments. To develop soil models that remain accurate at very high pressures there is a need for data on soil behaviour under these extreme conditions. This paper demonstrates the use of a high-pressure multi-axial test apparatus to provide compressibility and shear strength data for four dry sandy soils. One-dimensional compression experiments were performed to axial stresses of 800 MPa, where the effects of particle-size distribution were observed with respect to compressibility and bulk unloading modulus. Each soil followed a bilinear normal compression line (NCL): more uniform soils initially had higher compression indices, but all four NCLs began to converge at void ratios below e ≈ 0.3. The failure surface of a sand was characterized to mean effective stress [Formula: see text] > 400 MPa using reduced triaxial compression experiments, removing the need to rely on extrapolation from low-pressure data.

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