Density measurements of liquid Fe–Si alloys at high pressure using the sink–float method

In the present study, we present a novel method to sinter Cr3C2 powders under high pressure without any addittives. The sintering Cr3C2 samples were charaterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), relative density measurements, Vicker’s hardness tests and Fracture toughness tests. The reasults show that Cr3C2 powders could be sintered to be bulk under the conditions of 3-5 GPa, 800-1200 °C and the heat preservation for 15 min. Moreover, the sintering body of Cr3C2 compound with the relative density of 99.84% by simultaneously tuning the pressure-temperature conditions exhibited excellent mechanical properties: a Vickers hardness of 20.3 GPa and a fracture toughness of ~8.9 MPam1/2. These properties were much higher than that by using the previous methods. The temperature condition obtained good mechanical properties in the experiment was about 1/3 lower than that using any other methods owing to the high pressure.

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Thermoelastic properties of liquid Fe‐C revealed by sound velocity and density measurements at high pressure

Journal of Geophysical Research Solid Earth ◽

10.1002/2016jb012968 ◽

2016 ◽

Vol 121 (11) ◽

pp. 7984-7995 ◽

Cited By ~ 9

Author(s):

Yuta Shimoyama ◽

Hidenori Terasaki ◽

Satoru Urakawa ◽

Yusaku Takubo ◽

Soma Kuwabara ◽

...

Keyword(s):

High Pressure ◽

Sound Velocity ◽

Thermoelastic Properties ◽

Density Measurements

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High-temperature and high-pressure density measurements and other derived thermodynamic properties of 1-butyl-3-methylimidazolium tris (pentafluoroethyl) trifluorophosphate

Thermochimica Acta ◽

10.1016/j.tca.2017.10.022 ◽

2017 ◽

Vol 658 ◽

pp. 14-23 ◽

Cited By ~ 4

Author(s):

Javid Safarov ◽

Felix Lesch ◽

Khagani Suleymanli ◽

Abilgani Aliyev ◽

Astan Shahverdiyev ◽

...

Keyword(s):

High Pressure ◽

High Temperature ◽

Thermodynamic Properties ◽

Density Measurements

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Polymorphism of 1,3-X-adamantanes (X = Br, OH, CH3) and the crystal plastic phase formation ability

CrystEngComm ◽

10.1039/c9ce01910c ◽

2020 ◽

Vol 22 (7) ◽

pp. 1230-1238 ◽

Cited By ~ 1

Author(s):

Philippe Negrier ◽

Bacem Ben Hassine ◽

Maria Barrio ◽

Michela Romanini ◽

Denise Mondieig ◽

...

Keyword(s):

Differential Scanning Calorimetry ◽

High Pressure ◽

Phase Formation ◽

Powder Diffraction ◽

Scanning Calorimetry ◽

Density Measurements ◽

X Ray ◽

Plastic Phase

The polymorphism of 1,3-dimethyladamantane (13DMA), 1,3-adamantanediol (13DOHA) and 1,3-dibromoadamantane (13DBrA) has been studied by X-ray powder diffraction, density measurements and differential scanning calorimetry at normal and high-pressure.

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Density and composition of the lower mantle

Philosophical Transactions of the Royal Society of London. Series A, Mathematical and Physical Sciences ◽

10.1098/rsta.1989.0042 ◽

1989 ◽

Vol 328 (1599) ◽

pp. 377-389 ◽

Cited By ~ 102

Keyword(s):

High Pressure ◽

Density Distribution ◽

Upper Mantle ◽

Lower Mantle ◽

Mineral Assemblage ◽

Geophysical Data ◽

Density Difference ◽

Depth Range ◽

Density Measurements ◽

Mantle Composition

The observed density distribution of the lower mantle is compared with density measurements of the (M g,Fe)SiO 3 perovskite and (Mg,Fe)O magnesiowtistite highpressure phases as functions of pressure, tem perature and composition. We find that for plausible bounds on the composition of the upper mantle (ratio of magnesium to iron + magnesium components x M g ^ 0.88) and the temperature in the lower mantle ( T ^ 2000 K), the high-pressure mineral assemblage of upper-mantle composition is at least 2 .6 ( ± 1 ) % less dense than the lower m antle over the depth range 1000-2000 km. Thus, we find that a model of uniform m antle composition is incompatible with the existing mineralogical and geophysical data. Instead, we expect that the mantle is stratified, with the upper and lower m antle convecting separately, and we estimate that the compositional density difference between these regions is about 5 ( + 2) %. The stratification may not be perfect (‘leaky layering’), but significant intermixing and homogenization of the upper and lower m antle over geological timescales are precluded.

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