Composition, Structure, and Properties of a Composite Material Based on Polytetrafluoroethylene and Oxyfluoride Glass–Ceramic

The vitrification and crystallization of glasses in the system BaO(PbO)-B2O3-Al2O3-TiO2, containing (mol %): BaO (24.6-28.1 ), PbO (2.8-3.2), B2O3 (7.6-24.0), Al2O3 (15.9-25.5), TiO2 (39.1-41.1) were investigated. The batch compositions of different oxide molar ratios were fused in an electric furnace in a platinum crucible at 1450 ºC for 2 h and cast into cylindrical-shaped samples. The obtained glasses were crystallized at 950 ºC for 2h. BaTiO3 was recognized as a dominant crystalline phase in the produced glass-ceramic materials. The influence of B2O3 and Al2O3 contents on the chemical resistance, mechanical strength and dielectric properties was investigated. It is shown that the glass compositions containing (mol %): B203 7-25 and Al2O3 16-20 displayed the optimal combinations of exploitation properties. The influence of liquid phase separation on the abovementioned properties was also analyzed.

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Strengthening coatings on cutting tools (analytical review of international conference literature)

10.36652/1813-1336-2020-16-5-234-240 ◽

2020 ◽

pp. 234-240

Author(s):

V.A. Levchenko ◽

Yu.V. Panfilov

Keyword(s):

Cutting Tools ◽

International Standards ◽

Structure And Properties ◽

International Conference ◽

Analytical Review ◽

Composition Structure ◽

Analytical Equipment

Tendency of strengthening coatings on cutting tools processes evolution is analyzed. Manifold of strengthening materials, strengthening coatings deposition methods, process and analytical equipment for coatings manufacture and measurement of it’s properties is described. International standards for strengthening coatings on cutting tools composition, structure and properties are presented.

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Study of the Composite Materials Optimal Structure Containing a Hollow Aluminum and Silica Microsphere Dependence on Humidity

Micro and Nanosystems ◽

10.2174/1876402912999201109204218 ◽

2020 ◽

Vol 12 ◽

Author(s):

Alexandra Atyaksheva ◽

Yermek Sarsikeyev ◽

Anastasia Atyaksheva ◽

Olga Galtseva ◽

Alexander Rogachev

Keyword(s):

Composite Material ◽

Composite Materials ◽

Strength Function ◽

Theory And Practice ◽

Optimal Structure ◽

Optimal Size ◽

Structure And Properties ◽

Power Functions ◽

Silica Microsphere ◽

Heat Engineering

Aims:: The main goals of this research are exploration of energy-efficient building materials when replacing natural materials with industrial waste and development of the theory and practice of obtaining light and ultra-light gravel materials based on mineral binders and waste dump ash and slag mixtures of hydraulic removal. Background.: Experimental data on the conditions of formation of gravel materials containing hollow aluminum and silica microsphere with opportunity of receipt of optimum structure and properties depending on humidity with the using of various binders are presented in this article. This article dwells on the scientific study of opportunity physical-mechanical properties of composite materials optimization are considered. Objective.: Composite material contains hollow aluminum and silica microsphere. Method.: The study is based on the application of the method of separation of power and heat engineering functions. The method is based on the use of the factor structure optimality, which takes into account the primary and secondary stress fields of the structural gravel material. This indicates the possibility of obtaining gravel material with the most uniform distribution of nano - and microparticles in the gravel material and the formation of stable matrices with minimization of stress concentrations. Experiments show that the thickness of the cement shell, which performs power functions, is directly related to the size of the raw granules. At the same time, the thickness of the cement crust, regardless of the type of binder, with increasing moisture content has a higher rate of formation for granules of larger diameter. Results.: The conditions for the formation of gravel composite materials containing a hollow aluminosilicate microsphere are studied. The optimal structure and properties of the gravel composite material were obtained. The dependence of the strength function on humidity and the type of binder has been investigated. The optimal size and shape of binary form of gravel material containing a hollow aluminosilicate microsphere with a minimum thickness of a cement shell and a maximum strength function was obtained. Conclusion.: Received structure allows to separate power and heat engineering functions in material and to minimize the content of the excited environment centers.

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Nanostructured powders based on aluminum reinforced by silicon nitride designed for spraying of multifunctional strengthened coatings

Voprosy Materialovedeniya ◽

10.22349/1994-6716-2019-97-1-65-73 ◽

2019 ◽

pp. 65-73

Author(s):

T. I. Bobkova ◽

B. V. Farmakovsky ◽

N. A. Sokolova

Keyword(s):

Silicon Nitride ◽

Composite Powder ◽

High Energy ◽

Cold Gas Dynamic Spraying ◽

Powder Materials ◽

Structure And Properties ◽

Gas Dynamic ◽

Composition Structure ◽

New Phase ◽

Nanostructured Powders

The work deals with topical issues such as development of composite nanostructured powder materials. The results of creating powders based on the system “aluminum–nitride of silicon” are presented. Complex investigations of the composition, structure and properties of powder materials, as well as coatings formed on their basis by supersonic cold gas dynamic spraying, were carried out. It has been found that the high-energy treatment of a powder mixture of aluminum with nanofibers of silicon nitride provides the formation of a composite powder in which a new phase of the Si(1-х)AlхO(1-х)Nх type is formed, which additionally increases the hardness in the coatings to be sprayed.

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Composition, Structure, and Properties of the Electroerosive Powders Fabricated from the Wastes of a VNZh Alloy in Distilled Water

Russian Metallurgy (Metally) ◽

10.1134/s0036029520120034 ◽

2020 ◽

Vol 2020 (12) ◽

pp. 1423-1427

Author(s):

E. V. Ageev ◽

R. A. Latypov

Keyword(s):

Distilled Water ◽

Structure And Properties ◽

Composition Structure

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Influence of Applied Bias Voltage on the Composition, Structure, and Properties of Ti:Si-Codoped a-C:H Films Prepared by Magnetron Sputtering

Journal of Nanomaterials ◽

10.1155/2014/937068 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 3

Author(s):

Jinlong Jiang ◽

Qiong Wang ◽

Yubao Wang ◽

Zhang Xia ◽

Hua Yang ◽

...

Keyword(s):

Mechanical Properties ◽

Surface Roughness ◽

Magnetron Sputtering ◽

Bias Voltage ◽

Tribological Properties ◽

Structure And Properties ◽

Applied Bias ◽

Applied Bias Voltage ◽

Methane Mixture ◽

Composition Structure

The titanium- and silicon-codoped a-C:H films were prepared at different applied bias voltage by magnetron sputtering TiSi target in argon and methane mixture atmosphere. The influence of the applied bias voltage on the composition, surface morphology, structure, and mechanical properties of the films was investigated by XPS, AFM, Raman, FTIR spectroscopy, and nanoindenter. The tribological properties of the films were characterized on an UMT-2MT tribometer. The results demonstrated that the film became smoother and denser with increasing the applied bias voltage up to −200 V, whereas surface roughness increased due to the enhancement of ion bombardment as the applied bias voltage further increased. The sp3carbon fraction in the films monotonously decreased with increasing the applied bias voltage. The film exhibited moderate hardness and the superior tribological properties at the applied bias voltage of −100 V. The tribological behaviors are correlated to the H/E or H3/E2ratio of the films.

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