Combustion Synthesis on Mechanoactivated FeTi+C Powder Mixtures

Experimental results on the preparation of functionally graded TiC-based cermets obtained by combustion synthesis (also known as Self-Propagating High-Temperature Synthesis, SHS) followed by quasi-isostatic (QIP) pressing in a granulate medium are presented. Pellets of TiC-Fe graded cermets are produced by stacking layers of Ti and C powder mixtures in which the content of a NiFe alloy (50 wt% Ni and 50 wt% Fe) is varied from 5 up to 25 vol %. X-ray diffraction showed that the NiFe alloy did not react with the TiC, thus preserving its special properties. Scanning electron microscopy results show a graded material with pores increasing in size towards the side with the highest ceramic fraction.

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Combustion Synthesis of High-Energy Ball-Milled Nb + 3Al Powder Mixtures

Materials Science Forum ◽

10.4028/www.scientific.net/msf.416-418.156 ◽

2003 ◽

Vol 416-418 ◽

pp. 156-161 ◽

Cited By ~ 1

Author(s):

Ricardo Mendes Leal Neto ◽

Cláudio José da Rocha ◽

Francisco Ambrozio Filho

Keyword(s):

Combustion Synthesis ◽

High Energy ◽

Powder Mixtures ◽

Energy Ball

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Fabrication of Single-Phase NiTi by Combustion Synthesis of Mechanically Activated Powders

Journal of Metallurgy ◽

10.1155/2012/153841 ◽

2012 ◽

Vol 2012 ◽

pp. 1-6

Author(s):

S. Mousavi Nasab ◽

M. Aboutalebi ◽

S. H. Seyedein ◽

A. Molavi Kakhki ◽

J. Vahdati Khaki

Keyword(s):

Combustion Synthesis ◽

Ignition Temperature ◽

Ball Mill ◽

Single Phase ◽

Milling Time ◽

Time Profile ◽

X Ray Diffraction ◽

Powder Mixtures ◽

X Ray ◽

Temperature Time

Single-phase NiTi was fabricated through the thermal explosion mode of combustion synthesis of mechanically activated powders. Combustion and ignition temperatures of combustion synthesis were investigated in different milling times. In this process, equiatomic powder mixtures of nickel and titanium were activated by planetary ball mill and pressed into disk-shaped pellets then heated in a tube furnace, while temperature-time profile was recorded. X-ray diffraction analysis (XRD) was performed on milled powders as well as synthesized samples. Scanning electron microscopy (SEM) was also used to study the microstructural evolution during milling. The results showed that there was a threshold milling time to obtain single-phase NiTi. It was also seen that the ignition temperature and combustion temperature were reduced significantly by increasing milling time.

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Thermite reduction of Ta2O5/SiO2 powder mixtures for combustion synthesis of Ta-based silicides

Journal of Alloys and Compounds ◽

10.1016/j.jallcom.2011.03.063 ◽

2011 ◽

Vol 509 (21) ◽

pp. 6302-6306 ◽

Cited By ~ 8

Author(s):

C.L. Yeh ◽

Y.S. Huang

Keyword(s):

Combustion Synthesis ◽

Powder Mixtures ◽

Sio2 Powder

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Effect of mechanical alloying on combustion synthesis of MoSi2

Journal of Materials Research ◽

10.1557/jmr.2001.0423 ◽

2001 ◽

Vol 16 (11) ◽

pp. 3060-3068 ◽

Cited By ~ 10

Author(s):

Hyung-Sang Park ◽

Kwang-Seon Shin ◽

Yong-Seog Kim

Keyword(s):

Mechanical Alloying ◽

Combustion Synthesis ◽

Ignition Temperature ◽

Lamellar Structure ◽

Combustion Temperature ◽

Low Energy ◽

Combustion Reaction ◽

Diffusional Process ◽

Powder Mixtures ◽

Energy Ball

Characteristics of the combustion synthesis of MoSi2 using elemental Mo and Si powder mixtures prepared by mechanical alloying were investigated. The mechanical alloying resulted in powders of pseudolamellar structure and a partial conversion of the elemental powders to hexagonal MoSi2 phase. Combustion reaction of the mixture was ignited around 670 °C, which is much lower than that with the powder prepared by low-energy ball milling. A mathematical model was developed to demonstrate the possibility of the ignition of the combustion reaction of the lamellar structure via a solid-state diffusional process. On the basis of model, effects of mechanical alloying time on the ignition temperature and combustion temperature are discussed.

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Combustion Synthesis of Cu1-xNixCr2O4 Spinel for Catalytic Applications

Materials Science Forum ◽

10.4028/www.scientific.net/msf.498-499.663 ◽

2005 ◽

Vol 498-499 ◽

pp. 663-668 ◽

Cited By ~ 1

Author(s):

P.M. Pimentel ◽

M.F. Ginani ◽

Antonio Eduardo Martinelli ◽

D.M.A. Melo ◽

A.M. Garrido Pedrosa ◽

...

Keyword(s):

Combustion Synthesis ◽

Catalytic Combustion ◽

Fine Particles ◽

Particle Morphology ◽

X Ray Diffraction ◽

Powder Mixtures ◽

X Ray ◽

Heterogeneous Processes ◽

Different Temperatures ◽

Cost Efficient

Transition-metal spinels are efficient catalysts in a number of heterogeneous processes, such as CO oxidation, catalytic combustion of hydrocarbons and oxychlorination of methane. The properties of catalytic materials are highly dependent on the synthesis route. Spinels are often produced at high temperatures by the calcination of precursors such as powder mixtures, slurries or resins. Combustion synthesis is a cost-efficient method used to produce homogeneous and fine particles with high reproducibility. Cu0.8Ni0.2Cr2O4 spinel was obtained by the combustion of metallic nitrates using urea as fuel. The resulting powders were calcinated at different temperatures and characterized by thermogravimetric and particle size analyses, X ray diffraction, and scanning electron microscopy. The effect of urea on the control of the process and particle morphology was investigated. The results revealed the formation of porous powders with increasing crystallinity as the calcination temperature increased. Crystallization of spinel started at 700 oC.

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