Self-Propagating High-Temperature Synthesis of Boron-Containing MAX-Phase

2017 ◽  
Vol 746 ◽  
pp. 207-213 ◽  
Author(s):  
Aleksandr P. Amosov ◽  
Evgeniy I. Latukhin ◽  
P.A. Petrov ◽  
E.A. Amosov ◽  
Vladislav A. Novikov ◽  
...  
Keyword(s):  
High Temperature ◽  
Intermetallic Compound ◽  
Boron Content ◽  
Max Phase ◽  
X Ray Diffraction ◽  
Temperature Synthesis ◽  
Max Phases ◽  
X Ray ◽  
Titanium Borides ◽  
High Temperature Synthesis

An attempt was made to obtain boron-containing MAX-phase by the process of self-propagating high-temperature synthesis (SHS) of Ti3AlC2, replacing some carbon atoms by boron atoms. This was conducted by burning powder mixtures (charges) of the composition 3Ti+2Al+2((1-x)C+xB), where x is the fraction of boron atoms (0.10, 0.15, 0.25, 0.50, 0.75, 0.90), replacing the carbon atoms. X-ray diffraction analysis of the products of combustion have shown that the replacement of carbon with boron to half of the content of carbon atoms in the charge (x=0.10-0.50), does not change the phase composition of the products, including Ti3AlC2 and TiC, but leads to a shift of the peaks of these phases in the diffraction pattern in the direction of smaller angles. When replacing more than half of the carbon atoms with the boron (x=0.75 and 0.90), the peaks of titanium carbide and MAX-phase are not observed, and the XRD peaks appear of the titanium borides TiB and TiB2, and intermetallic compound Al3Ti. Photomicrographs obtained with an electron microscope show that the SHS products synthesized from the charge with replacing up to half of the carbon atoms with the boron represent plates with a thickness of about 1 μm typical for MAX-phases, but rounded particles of borides and intermetallic compound of titanium appear at a higher boron content. Based on these results, it is concluded that replacement of a part (up to 50%) of the carbon atoms with boron atoms in the SHS charge 3Ti+2Al+2C leads to the synthesis of boron-containing MAX-phase based on the crystal lattice of Ti3AlC2.

A Study of Fe-Based Composite Coating Fabricated by the Self-Propagating High Temperature Synthesis

2012 ◽  
Vol 626 ◽  
pp. 138-142
Author(s):  
Saowanee Singsarothai ◽  
Vishnu Rachpech ◽  
Sutham Niyomwas
Keyword(s):  
High Temperature ◽  
Composite Coating ◽  
Steel Substrate ◽  
The Self ◽  
X Ray Diffraction ◽  
Temperature Synthesis ◽  
X Ray ◽  
High Temperature Synthesis ◽  
Precursor Powders ◽  
Scanning Electron

The steel substrate was coated by Fe-based composite using self-propagating high-temperature synthesis (SHS) reaction of reactant coating paste. The green paste was prepared by mixing precursor powders of Al, Fe2O3and Al2O3. It was coated on the steel substrate before igniting by oxy-acetylene flame. The effect of coating paste thickness and the additives on the resulted Fe-based composite coating was studied. The composite coating was characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM) couple with dispersive X-ray (EDS).

Self-Propagating High-Temperature Synthesis of Fe-W(B, C) Based Composite

2013 ◽  
Vol 748 ◽  
pp. 46-50 ◽  
Author(s):  
Saowanee Singsarothai ◽  
Sutham Niyomwas
Keyword(s):  
Electron Microscope ◽  
High Temperature ◽  
Scanning Electron Microscope ◽  
The Self ◽  
X Ray Diffraction ◽  
Temperature Synthesis ◽  
X Ray ◽  
High Temperature Synthesis ◽  
Flame Ignition ◽  
Scanning Electron

Fe-W based composite have successfully been prepared using natural resource. The ferberite (Fe (Mn, Sn)WO4) tailings mixed with aluminum, carbon and boron oxide powder were used as reactants. The reactants were pressed and followed by oxy-acetylene flame ignition. The products from the self-propagating high-temperature synthesis (SHS) reaction were characterized by X-ray diffraction (XRD) and scanning electron microscope (SEM) couple with dispersive X-ray (EDS).

Microstructure and Wear Performance of Cu-Mo-Si Alloys Fabricated by Self-Propagation High-Temperature Synthesis

2010 ◽  
Vol 658 ◽  
pp. 408-411
Author(s):  
Hui Xie ◽  
Lei Jia ◽  
Si Ming Wang ◽  
Ji Ling Zhu ◽  
Zhen Lin Lu
Keyword(s):  
High Temperature ◽  
Wear Behavior ◽  
X Ray Diffraction ◽  
Temperature Synthesis ◽  
Wear Performance ◽  
X Ray ◽  
Cu Content ◽  
High Temperature Synthesis ◽  
Pin On Disc ◽  
Worn Surface

Cu-Mo-Si alloys with different Cu contents were prepared by self-propagation high-temperature synthesis (SHS). The microstructure and the worn surface morphology were observed using scanning electron microscopy (SEM) together with energy dispersive X-ray spectroscopy (EDS) analysis. Phase composition was determined by X-ray diffraction (XRD). The wear behavior of the Cu-Mo-Si alloys was characterized by pin-on-disc wear tester. The results showed that most of Si atoms dissolved in Cu matrix or resulted in formation of compound with Cu, while only small amount of Si atoms reacted with Mo atoms to form Mo5Si3 particles in the Cu-Ni-Si alloys with 80% Cu content. The wear rate of Cu-Mo-Si alloys descended with a decrease of Cu content, and the predominant wear mechanism could be identified as abrasive wear for Cu content less than 90% and plastic deformation for Cu content higher than 90%.

Synthesis of WSi2-W5Si3 Intermetallic Alloy via Self-Propagating High Temperature Synthesis

2018 ◽  
Vol 280 ◽  
pp. 121-126
Author(s):  
Si Thu Myint Maung ◽  
Tawat Chanadee ◽  
Sutham Niyomwas
Keyword(s):  
High Temperature ◽  
Energy Minimization ◽  
Standard Gibbs Energy ◽  
Equilibrium Composition ◽  
Intermetallic Alloy ◽  
X Ray Diffraction ◽  
Temperature Synthesis ◽  
Minimization Method ◽  
X Ray ◽  
High Temperature Synthesis

Intermetallic alloy of tungsten silicide (WSi2-W5Si3) was synthesized by self-propagating high temperature synthesis (SHS) from the reactant of tungsten oxide (WO3) and silicon lump (Si) using magnesium (Mg) as fuel. The standard Gibbs energy minimization method was used to calculate the equilibrium composition of the possible reacting species. The as-SHS products were characterized by X-ray diffraction (XRD) technique. The magnesiothermic reaction process successfully synthesized dense of WSi2-W5Si3intermetallic alloy. According to the experimental results, it can be proposed that the reaction also promotes the phase separation between alloy and oxide slag of the product.

A time-resolved x-ray diffraction study of Ti5Si3 product formation during combustion synthesis

1997 ◽  
Vol 12 (12) ◽  
pp. 3230-3240 ◽  
Author(s):  
C. R. Kachelmyer ◽  
I. O. Khomenko ◽  
A. S. Rogachev ◽  
A. Varma
Keyword(s):  
Thermal Expansion ◽  
High Temperature ◽  
Product Formation ◽  
X Ray Diffraction ◽  
Temperature Synthesis ◽  
Time Resolved ◽  
X Ray ◽  
Thermal Expansion Coefficients ◽  
High Temperature Synthesis ◽  
Expansion Coefficients

Time-resolved x-ray diffraction (TRXRD) was performed during Ti5Si3 synthesis by the self-propagating high-temperature synthesis mode for different Ti size fractions. It was determined that the time for product formation (ca. 15 s) was independent of Ti particle size. However, the formation of Ti5Si4 phase occurred when relatively large titanium particles were used. A simultaneous measurement of the temperature and TRXRD allowed us to attribute the shifting of XRD peaks at high temperature to thermal expansion of the Ti5Si3 product. The thermal expansion coefficients differ for different crystal planes, and their numerical values compare well with those reported previously in the literature.

Microstructure of Ni-Al-Diamond Composite Fabricated by Self-Propagating High Temperature Synthesis

2005 ◽  
Vol 291-292 ◽  
pp. 531-536 ◽  
Author(s):  
Feng Lin Zhang ◽  
Hui Yuan ◽  
Cheng Yong Wang ◽  
K.X. Fu ◽  
Y.M. Zhou
Keyword(s):  
High Temperature ◽  
Diamond Tool ◽  
Vacuum Furnace ◽  
X Ray Diffraction ◽  
Muffle Furnace ◽  
Temperature Synthesis ◽  
Diamond Composite ◽  
X Ray ◽  
High Temperature Synthesis ◽  
Scanning Electron

Diamond tool based on Ni-Al self-propagating high temperature synthesis (SHS) was introduced in this paper. Different heating methods such as muffle furnace, vacuum furnace and induction were used to ignite the Ni-Al-diamond SHS system. The morphology and microstructure of the Ni-Al-diamond composite were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM). It was found that SHS Ni-Al-diamond composite ignited by induction heating owned the best morphology and microstructure to work as diamond tool.

Effect of Al Mole Ratio on Iron Aluminide Reinforced with TiB2-Al2O3 Composite by Self-Propagating High-Temperature Synthesis

2012 ◽  
Vol 488-489 ◽  
pp. 305-309 ◽  
Author(s):  
Kunyaporn Tapsuan ◽  
Sutham Niyomwas
Keyword(s):  
High Temperature ◽  
Standard Gibbs Energy ◽  
Iron Aluminide ◽  
Molar Ratio ◽  
X Ray Diffraction ◽  
Temperature Synthesis ◽  
Minimization Method ◽  
X Ray ◽  
Optimum Result ◽  
High Temperature Synthesis

The Fe3Al-TiB2-Al2O3 composite has been prepared by self-propagating high-temperature synthesis (SHS) from FeTiO3-B2O3-Al system. The standard Gibbs energy minimization method was used to calculate the equilibrium compositions of the reacting species. The reactions were carried out in a SHS reactor under static argon gas at the pressure of 0.5 MPa. The effects of Al molar ratio of 4, 4.33 and 5 mole on the results product were investigated. The composition and microstructure of SHS products were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX). The optimum result of Fe3Al intermetallics phase was obtained when using 4.33 mole of Al.

scholarly journals Self-Propagating High-Temperature Synthesis of Chromium Substituted Lanthanide – Barium – Copper Oxides, LnBa2Cu3-xCrxO7-y (Ln = Y; La; Nd; Sm and Yb)

2017 ◽  
Vol 4 (2) ◽  
pp. 73 ◽  
Author(s):  
Maxim V. Kuznetsov ◽  
Ivan P. Parkin ◽  
Yuri G. Morozov ◽  
Alexander G. Merzhanov
Keyword(s):  
Magnetic Susceptibility ◽  
High Temperature ◽  
Sodium Perchlorate ◽  
Earth Metal ◽  
X Ray Diffraction ◽  
Temperature Synthesis ◽  
X Ray ◽  
High Temperature Synthesis ◽  
Barium Copper ◽  
Chromium Substitution

<p>A series of MBa<sub>2</sub>Cu<sub>3-x</sub>CrxO<sub>7-y</sub> (M = Y; La; Nd; Sm and Yb; <em>x </em>= 0, 0.05, 0.15, 0.25) materials were synthesized in air by self-propagating high-temperature synthesis (SHS) involving reaction of stoichiometric mixtures of rare-earth metal (III) oxide, barium peroxide, copper metal, chromium (III) oxide and sodium perchlorate. All the SHS processes were followed by sintering in oxygen at 950 °C for 2h. The products were characterized by SEM, X-ray powder diffraction, UV, superconductive transition temperatures (T<sub>c</sub>) and magnetic susceptibility (χ) measurements. X-ray diffraction data showed that single phase orthorhombic (or tetragonal for M = Nd) materials were produced. All series of materials showed a systematic increase in lattice parameters and unit cell volume with chromium content (M = Y: <em>x </em>= 0, <em>V </em>= 174.25 Å3; <em>x </em>= 0.25, <em>V </em>= 175.10 Å3). Thermal stability of all the SHS prepared materials increased with <em>x</em>. Oxygen content of all the samples increased with <em>x</em>, but did not exceed 7.0. Superconductivity transition temperature decreased with chromium substitution in all systems (98-77 K). Magnetic susceptibility decreased with chromium substitution.</p>

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