Modeling the instantaneous phase composition of cement pastes under elevated temperatures

The article presents results of a study of phase composition and microstructure of initial material and samples obtained by selective laser melting of titanium-based alloy, as well as samples after heat treatment. The effect of heat treatment on microstructure and mechanical properties of specimens was shown. It was studied mechanical behavior of manufactured specimens before and after heat treatment at room and elevated temperatures as well. The heat treatment allows obtaining sufficient mechanical properties of material at room and elevated temperatures such as increase in ductility of material. The fractography of samples showed that they feature ductile fracture with brittle elements.

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INTERMETALLIC COMPOUND AlxTi – ARE PROMISING MATERIAL FOR HIGH ELEVATED TEMPERATURES (review) Part 2. The mechanical properties of the intermetallic Al2Ti compound and the effect of alloying

Proceedings of VIAM ◽

10.18577/2307-6046-2021-0-4-32-47 ◽

2021 ◽

pp. 32-47

Author(s):

N.A. Nochovnaya ◽

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V.I. Ivanov ◽

L.Yu. Avilochev ◽

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...

Keyword(s):

Mechanical Properties ◽

Phase Composition ◽

Intermetallic Compound ◽

Elevated Temperatures ◽

Niobium Alloy ◽

Promising Material ◽

Two Phase ◽

Heat Resistant ◽

Refractory Elements ◽

Additional Doping

Intermetallide alloys based on the Al2Ti compound are the most promising heat-resistant materials for future energy plants.The review examines the mechanical properties of the Al2Ti Intermetalide, two-phase alloys based on it and the doped niobium alloy. For use at temperatures of up to 950 °С, alloys with phase composition r-Al2Ti + γ-TiAl and platemicrostructure with additional doping of refractory elements are of interest.

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Studying of Microstructure and Properties of Selective Laser Melted Titanium-Based Alloy

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1120-1121.1269 ◽

2015 ◽

Vol 1120-1121 ◽

pp. 1269-1275

Author(s):

Anatoly A. Popovich ◽

Vadim Sh. Sufiiarov ◽

Igor A. Polozov ◽

Evgenii V. Borisov ◽

Maxim Y. Maximov

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Phase Composition ◽

Mechanical Behavior ◽

Selective Laser Melting ◽

Powder Material ◽

Elevated Temperatures ◽

Initial Powder ◽

Laser Melting ◽

Before And After

The article presents the results of selective laser melting of Ti-6Al-4V alloy. It was studied phase composition and microstructure of the initial powder material, the specimens manufactured by Selective Laser Melting and also the specimens after heat treatment. The effect of heat treatment on microstructure and mechanical properties of the specimens was shown. It was studied the mechanical behavior of the manufactured specimens before and after heat treatment at room and elevated temperatures as well. After heat treatment tests showed that the specimens have decent mechanical properties both at room and elevated temperatures.

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Evolution of the phase composition of ZrB2-35MoSi2-15Al composite coating at annealing

Journal of Physics Conference Series ◽

10.1088/1742-6596/2124/1/012016 ◽

2021 ◽

Vol 2124 (1) ◽

pp. 012016

Author(s):

I Goncharov ◽

M Kovaleva ◽

M Yapryntsev ◽

V Sirota

Keyword(s):

Phase Composition ◽

Zirconium Dioxide ◽

Elevated Temperatures ◽

Silicon Oxide ◽

Composite Coatings ◽

Molybdenum Disilicide ◽

Carbon Composite ◽

Carbon Composites ◽

X Ray

Abstract In this article, new composite coatings ZrB2-35MoSi2-15Al were deposited on the surface of a carbon-carbon composite using a multi-chamber detonation accelerator. The evolution of the phase composition of ZrB2-35MoSi2-15Al coatings was analyzed with differential scanning calorimeter (DSC) and X-ray diffractometry (in situ HT-XRD) at temperatures from room temperature (∼ 25°C) to 1400°C (normal atmosphere and pressure). The coating before annealing according to X-ray diffractometry data is tetragonal (t-ZrO2) and monocline (m-ZrO2) zirconium dioxide, monocline silicon oxide (m-SiO2), hexagonal zirconium diboride (h-ZrB2), tetragonal molybdenum disilicide (t-MoSi2), cubic aluminum (c-Al) and cubic yttrium oxide (c-Y2O3). It was found that the coating crystallizes in m-ZrO2 at 460ºC, and then mullite with rhombic crystal lattice appears at 960ºC. When the temperature reaches 1050ºC the m-ZrO2, ZrSiO4, t-ZrO2, m-SiO2 and mullite phases formed in the coating. At 1400 º C, cubic zirconium dioxide appears in the coating. Experimental results can become the basis for the application of ceramic coating ZrB2-35MoSi2-15Al, which can improve the properties of carbon-carbon composites in an oxygen-containing environment at elevated temperatures.

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Phase Transitions of Polarised PVDF Films in a Standard Curing Process for Composites

Polymers ◽

10.3390/polym13223900 ◽

2021 ◽

Vol 13 (22) ◽

pp. 3900

Author(s):

Nils Vasic ◽

Julian Steinmetz ◽

Marion Görke ◽

Michael Sinapius ◽

Christian Hühne ◽

...

Keyword(s):

Phase Composition ◽

Elevated Temperatures ◽

Phase Changes ◽

Curing Process ◽

Melting Range ◽

New Methods ◽

Β Phase ◽

Α Phase ◽

Laminated Structures ◽

Film Annealing

The article reports on the influence of annealing PVDF in an autoclave process on the PVDF phase composition. DSC, FTIR and XRD measurements serve to observe the phase changes in an already stretched, polarised and β-phase rich film. Annealing was conducted between 90 and 185 ∘C to cover a broad range of curing processes in an autoclave. The β-phase is found to be stable up to near the melting range at 170 ∘C. At 175 ∘C, the non-piezoelectric α-phase dominates and the piezoelectric γ- and γ′-phases appear. The γ-phase grows at elevated temperatures and replaces the β-phase. This observation stresses the importance of developing new methods to reactivate the polarisation after annealing, in particular for the integration of PVDF as a sensor in laminated structures, such as CFRP.

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