Properties of Copper and Molybdenum Sulfide Powders Produced by Self-Propagating High-Temperature Synthesis

Copper and molybdenum sulfide nanopowders were prepared by self-propagating high-temperature synthesis in argon. The initial copper powder and molybdenum powder were produced by electric spark dispersion in hexane and by electrical explosion of wires (EEW) in argon, respectively. The powders were studied by electron microscopy, X-ray diffraction and Raman spectroscopy. The copper sulfide main phase is hexagonal 2H-CuS, whereas hexagonal 2H-MoS2 and rhombohedral 3R-MoS2 are characteristic for molybdenum disulfide. The lattice parameters of copper and molybdenum sulfides were calculated. The average particle size of copper sulfide and molybdenum disulfide powders was about 50 nm and 80 nm, respectively.

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Tribological Properties of Nanolamellar MoS2Doped with Copper Nanoparticles

Journal of Nanomaterials ◽

10.1155/2014/731073 ◽

2014 ◽

Vol 2014 ◽

pp. 1-7 ◽

Cited By ~ 5

Author(s):

Vladimir An ◽

Yuri Irtegov

Keyword(s):

High Temperature ◽

Molybdenum Disulfide ◽

Copper Nanoparticles ◽

Tribological Properties ◽

Electrical Explosion ◽

Elementary Sulfur ◽

Molybdenum Powder ◽

Temperature Synthesis ◽

High Temperature Synthesis ◽

Electrical Explosion Of Wires

This study aimed at examining the tribological properties of nanolamellar molybdenum disulfide doped with copper nanoparticles. Nanolamellar molybdenum disulfide was produced using self-propagating high-temperature synthesis via the reaction between elementary sulfur and nanosized molybdenum powder prepared by electrical explosion of wires. Copper nanoparticles were also prepared by electrical explosion of copper wires. Comparative tribological tests were carried out for nanolamellar and commercial molybdenum disulfides doped with 7 wt.% of copper nanoparticles. It was demonstrated that doping copper nanoparticles additives reduce wear of the friction body when using both commercial and nanolamellar molybdenum disulfide.

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High-Temperature Synthesis of Metal–Matrix Composites (Ni-Ti)-TiB2

Applied Sciences ◽

10.3390/app11052426 ◽

2021 ◽

Vol 11 (5) ◽

pp. 2426

Author(s):

Vladimir Promakhov ◽

Alexey Matveev ◽

Nikita Schulz ◽

Mikhail Grigoriev ◽

Andrey Olisov ◽

...

Keyword(s):

High Temperature ◽

Composite Materials ◽

Metal Matrix Composite ◽

Matrix Composite ◽

Metal Matrix ◽

Average Particle Size ◽

Synthesis Process ◽

Average Particle ◽

Temperature Synthesis ◽

High Temperature Synthesis

Currently, metal–matrix composite materials are some of the most promising types of materials, and they combine the advantages of a metal matrix and reinforcing particles/fibres. Within the framework of this article, the high-temperature synthesis of metal–matrix composite materials based on the (Ni-Ti)-TiB2 system was studied. The selected approaches make it possible to obtain composite materials of various compositions without contamination and with a high degree of energy efficiency during production processes. Combustion processes in the samples of a 63.5 wt.% NiB + 36.5 wt.% Ti mixture and the phase composition and structure of the synthesis products were researched. It has been established that the synthesis process in the samples proceeds via the spin combustion mechanism. It has been shown that self-propagating high-temperature synthesis (SHS) powder particles have a composite structure and consist of a Ni-Ti matrix and TiB2 reinforcement inclusions that are uniformly distributed inside it. The inclusion size lies in the range between 0.1 and 4 µm, and the average particle size is 0.57 µm. The obtained metal-matrix composite materials can be used in additive manufacturing technologies as ligatures for heat-resistant alloys, as well as for the synthesis of composites using traditional methods of powder metallurgy.

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Nickel-Containing Systems in Reaction of Partial Oxidation of Hydrocarbons

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.670.33 ◽

2015 ◽

Vol 670 ◽

pp. 33-38 ◽

Cited By ~ 1

Author(s):

Sergey Galanov ◽

Olga I. Sidorova ◽

Vera A. Batyreva

Keyword(s):

High Temperature ◽

Average Particle Size ◽

Reaction Medium ◽

Oxide Phase ◽

Average Particle ◽

Catalytic Layer ◽

Temperature Synthesis ◽

High Temperature Synthesis ◽

Catalytically Active ◽

Catalyst Systems

Nickel dispersion, which provides total catalytically active metal surface, is significant for partial catalytic oxidation of natural gas to obtain high purpose products yield and productivity in syngas. The interaction of reaction medium under high reaction temperatures during 20-25 hours promotes the increase of total square of active Ni component for block catalysts obtained with self-propagating high-temperature synthesis, which allows achieving productivity in syngas 7.1·103cm3(syngas)/cm3(catalyst)·hour. It is observed that for catalyst systems obtained with precipitation, chemical composition of oxide phase influences the particles size of metal nickel. For granular catalysts obtained through precipitation after 25-hour exploitation, average particle size (according to CSR) metal nickel is 3-4.5 times smaller than Ni in catalysts obtained with self-propagating high-temperature synthesis. This allows achieving productivity in syngas 8.1·103cm3/сm3·hour, when there is average temperature decrease over the catalytic layer by ~100°С in comparison with blocks acquired through self-propagating high-temperature synthesis.

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Self-Propagating High-Temperature Synthesis of Silicon Carbide and Silicon Nitride Nanopowders Composition using Sodium Azide and Halides

Eurasian Chemico-Technological Journal ◽

10.18321/ectj167 ◽

2013 ◽

Vol 16 (1) ◽

pp. 41 ◽

Cited By ~ 2

Author(s):

Yu.V. Titova ◽

A.P. Amosov ◽

G.V. Bichurov ◽

D.A. Maidan

Keyword(s):

Silicon Carbide ◽

High Temperature ◽

Silicon Nitride ◽

Combustion Synthesis ◽

Sodium Azide ◽

Average Particle Size ◽

Average Particle ◽

Temperature Synthesis ◽

High Temperature Synthesis ◽

Working Volume

Regularities of self-propagating high-temperature synthesis (SHS) or combustion synthesis (CS) by using “silicon – sodium azide – ammonium hexafluorosilicate – carbon – aluminum” powder mixture in the nitrogen atmosphere were investigated. The thermodynamic analysis of the combustion synthesis was performed. Experimental investigation of the combustion process: the measurement of linear rates of the combustion front propagation and the maximum combustion temperatures was conducted in a laboratory reactor with working volume 4.5 liters. The influence of the components ratio in the initial mixture on the combustion temperature, combustion rate and composition of reaction product was studied. The phase composition of the product synthesized was determined with an X-ray diffractometer. It was disclosed that the SHS product consists of the composition (mixture) of silicon carbide nanopowder with silicon nitride whiskers and a final halide. Investigation of surface topography and morphology of the product particles was carried out with a scanning electron microscope. Optimal mixture for the synthesis of nanoscale composition based on silicon carbide was determined: “14Si+6NaN3+(NH4)2SiF6+15C+Al”. In this case, the SHS product consists of four phases: silicon carbide (β-SiC) – 48.57 wt.%, α-silicon nitride (α-Si3N4) – 27.04 wt.%, β-silicon nitride (β-Si3N4) – 5.83 wt.%, and sodium hexafluoroaluminate (Na3AlF6) – 18.56 wt.%. The average particle size of the composition was in the range of 70–130 nm. It was shown that the composition of the silicon carbide with silicon nitride and the final halide Na3AlF6 playing a role a flux can be used as a modifier of castable aluminum alloys and as a reinforcing phase of aluminomatrix composites.

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Self-Propagating High-Temperature Synthesis of TiB2-Ti(C, N) Cermets Composite Powder

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.468-471.1247 ◽

2012 ◽

Vol 468-471 ◽

pp. 1247-1250 ◽

Cited By ~ 5

Author(s):

Fang Yang ◽

Zhi Meng Guo ◽

Jun Jie Hao ◽

Yong Liang Shi

Keyword(s):

Particle Size ◽

High Temperature ◽

Average Particle Size ◽

Average Particle ◽

X Ray Diffraction ◽

Composite Powders ◽

Temperature Synthesis ◽

High Temperature Synthesis ◽

Ni Addition ◽

Brittle Phase

The ultra-fine TiB2-Ti(C, N) composite powders were prepared by self-propagating high-temperature synthesis (SHS) with Ti, BN and C powders as its starting materials. The morphology of the products was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM). The results showed the composite powders were consisted of the mainly phases Ti(C, N), TiB2 and a small amount of TiN phase. With the Ni addition, the brittle phase Ni3B was appeared. SEM results revealed that the composite powders had a uniform particle size, a round grain-shaped structure and a narrow size distribution and the average particle size of which is less than 1μm.

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Self-Propagating High-Temperature Synthesis of Carbide- and Boride-Aluminides

Advances in Science and Technology ◽

10.4028/www.scientific.net/ast.45.1024 ◽

2006 ◽

Vol 45 ◽

pp. 1024-1028 ◽

Cited By ~ 4

Author(s):

Kiyotaka Matsuura ◽

Yusuke Hikichi ◽

Yuki Obara

Keyword(s):

Particle Size ◽

High Temperature ◽

Hot Isostatic Pressing ◽

Average Particle Size ◽

Average Particle ◽

Temperature Synthesis ◽

Powder Mixtures ◽

High Temperature Synthesis ◽

Tic Particle ◽

Tib2 Particles

TiC- and TiB2-FeAl composites have been produced using the Self-propagating High-temperature Synthesis (SHS) method under Pseudo Hot Isostatic Pressing (PHIP). When mixtures of the elemental powders were heated to a temperature near the melting point of Al under a PHIP of 150 MPa, the powder mixtures exothermically reacted and produced TiC particle dispersed and TiBB2 particle dispersed FeAl-matrix composites. As the volume factions of TiC and TiB2 particles increased from 0.3 to 0.8, the average particle size increased from approximately 1 to 10 μm and the average Vickers hardness increased from approximately 600 to 1600 in both the TiC-FeAl and TiB2-FeAl systems. The application of the PHIP remarkably reduced the porosity of the SHS products. Preheating of the elemental powder mixtures at 773 K for 30 minutes also reduced the porosity. Moreover, the preheating reduced the particle size in the SHS products. It was suggested that degassing of the powder surfaces and mutual diffusion between the different powders should have occurred during the preheating, which led to reduction in pore formation and reduction in heat generation at the SHS reactions, respectively.

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SHS and Properties of Perovskite La0.7Sr0.3MnO3 Powders by Using Dual Oxidants

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.287-290.671 ◽

2011 ◽

Vol 287-290 ◽

pp. 671-674

Author(s):

Xue Min Yan ◽

Yuan Zhu Mi ◽

Lin Xiong

Keyword(s):

Solid Oxide Fuel Cells ◽

Average Particle Size ◽

Complex Oxide ◽

Sintered Sample ◽

Second Phase ◽

Average Particle ◽

Temperature Synthesis ◽

High Temperature Synthesis ◽

Spark Plasma ◽

C 30

Self-propagating High-temperature Synthesis (SHS) was used to prepare complex oxide La0.7Sr0.3MnO3, which is used as the cathode in solid oxide fuel cells (SOFCs). Experiments show that La0.7Sr0.3MnO3 can be prepared via SHS under moderate conditions from a mixture of La2O3-SrO2-Mn-NaClO4-KMnO4，using NaClO4-KMnO4 as dual oxidants. The proper addition of the second phase oxidant KMnO4 makes the combustion wave movement stable. The product powders have an average particle size of 1-2μm and the particles are small aggregate. Pellets were sintered at 900 °C, 30 MPa for 10 min by spark plasma sinter (SPS). The electrical conductivity of sintered sample was 170 S•cm-1 at 1000 °C in air.

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Production of Al2O3/SiC Nanoparticles from Rice Husk Ash by Self-Propagating High-Temperature Synthesis Process and Ball Milling

Materials Science Forum ◽

10.4028/www.scientific.net/msf.904.93 ◽

2017 ◽

Vol 904 ◽

pp. 93-97 ◽

Cited By ~ 1

Author(s):

Morteza Hoseini ◽

Ghasem Dini ◽

Azam Fatemi

Keyword(s):

Particle Size ◽

High Temperature ◽

Ball Milling ◽

Rice Husk ◽

Rice Husk Ash ◽

Synthesis Process ◽

Average Particle ◽

Temperature Synthesis ◽

Sic Nanoparticles ◽

High Temperature Synthesis

In this study, silica obtained from the rice husk was used to synthesis of Al2O3/SiC nanoparticles. For this reason, the ash obtained from the burning of the rice husk which contains more than 93 wt. % silica, aluminum and carbon powders with the molar ratios of 3:4:6 were mixed and then compacted into pellets by using a cylindrical die under a pressure 50MPa. In order to conduct the self-propagating high-temperature synthesis (SHS), the produced pellets were placed in an electrical furnace at 850°C under the argon gas atmosphere. Then, a planetary ball milling for 4 to 24h was used to decrease the particle size of the synthesized composite. The results of XRF, XRD, SEM and DLS investigations shown that the rice husk ash can be used to fabricate Al2O3/SiC nanoparticles with an average particle size of about 80 to 65nm via SHS process and ball-milling for 12 to 24h.

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Planetary Milling and Self-Propagating High-Temperature Synthesis of Al-TiB2 Composites

Materials ◽

10.3390/ma13051050 ◽

2020 ◽

Vol 13 (5) ◽

pp. 1050 ◽

Cited By ~ 2

Author(s):

Alexey Matveev ◽

Ilya Zhukov ◽

Mansur Ziatdinov ◽

Alexander Zhukov

Keyword(s):

Powder Mixture ◽

Average Particle Size ◽

Aluminum Matrix ◽

Average Particle ◽

Initial Powder ◽

Time Increase ◽

Reaction Products ◽

Temperature Synthesis ◽

High Temperature Synthesis ◽

Powder Particles

The paper explores the influence of planetary milling on the temperature and velocity of Al-Ti-B powder mixture combustion and also on the structure and phase composition of the reaction products. It is found that the time increase of planetary milling modifies the structure of the powder particles, improves the density of compacted specimens, and increases the temperature and velocity of their combustion. These time dependences are extreme, with maximum values during 180 s planetary milling. Experiments show that the reaction products consist of an aluminum matrix with uniformly distributed particles of titanium diboride of not over 1 µm in size. The average particle size changes with the increase in the time of the planetary milling of the initial powder mixture.

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