Characteristics of the hydrogen-chlorine flame and the effect of different parameters for the synthesis of tungsten powders

Revankar, Vithal; Zhao, Guangyuan; Hlaváček, Vladimír

doi:10.1021/ie00058a015

Cited by 5 publications

(3 citation statements)

References 8 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Previous attempts to reach that objective have been unsuccessful because there has not been a reliable method availab1e to produce the ultrafine starting powders. [33] Mechanical milling, [34] liquid phase synthesis, [35], [36] chemical vapor deposition (CVD), [37], [38] and gas-to particle conversion methods [22,39,40,41] are possible sources of ultrafine W powders. Among these processes, flame synthesis has by far the highest possible production rates.…”

Section: Need For Nanosized W and W-ti Particlesmentioning

confidence: 99%

“…In this work, an inverted coflow burner was employed to obtain submicron metal powder by hydrogen reduction of WCl 6 . Future studies involved reacting tungsten halides in H 2 /F 2 [40] or H 2 /Cl 2 [41] flames. These approaches successfully produce W metal.…”

Section: Need For Nanosized W and W-ti Particlesmentioning

confidence: 99%

“…Long-chain hard agglomerates were usually formed [22] (Figure l-6) and the pure metal W powders were often pyrophoric, or oxide contamination formed on exposure to atmosphere. [41]…”

Section: Need For Nanosized W and W-ti Particlesmentioning

confidence: 99%

See 2 more Smart Citations

Montecarlo Simulation of Two Component Aerosol Processes

Huertas¹

2016

View full text Add to dashboard Cite

Associate professor at Los Andes University until 2002. Currently, full time professor at Tecnológico de Monterrey, Mexico. Has leaded the Energy Research Group in Colombia and the Automotive Engineering Research Center-CIMA in Mexico. Has published 45 papers mainly related to combustion and air pollution. Has graduated 6 PhD and 61 MSc. students. Has completed 90 research projects financed by private companies and governmental institutions. Currently works as researcher of the Energy and Climate Change Group of the School of Science and Engineering at Tecnológico de Monterrey. Is member of the national system of researcher in both Mexico and Colombia. PrefaceNanophase materials also referred to as nanostructured, nanocrystalline, or nanometer-sized crystalline solids, are single-phase or multiphase polycrystals, with dimensions of the order of 1-100 nm. Compared to conventional materials, nanophase materials possess unique advantages with respect to properties and processing. As grain size decreases down to the nanometer-size range, nanophase metals generally get stronger and harder, while nanophase ceramics show ductility, even superplasticity, at lower temperatures than conventional brittle ceramics. For example, 1000% increase in fracture stress, 2000% increase in magnetic susceptibility, 25% decrease in density, and 165% improvement in critical temperature for superconductivity have been observed in nanophase metals.The high-performance properties exhibited by nanophase materials have important implications for industry. For example, several tool companies are expected to introduce stronger, tougher, long-lasting cutting tools, drill bits, and wear parts composed of ultrafine grain cobalt/tungsten carbide composites. Some nanocomposites exhibit an unusual magnetic behavior called "giant magnetoresistance," which is being considered for read/write information in storage devices and to make improved magnetoresistive sensors. Another application under consideration is solid-state magnetic refrigerators based on the mega caloric effect by which heat is reversibly absorbed and discharged when small ferromagnetic particles are aligned by magnetic fields. In addition, unusual magneto-optical characteristics of nanostructured iron oxide are expected to be applicable for high definition color copiers. This book describes a novel method for the production of high purity, unagglomerated nano-particulates of tungsten (W) and tungsten titanium alloys (W-Ti) by flame synthesis. These materials possess unique properties that make them desirable for advanced applications.W-Ti nano-sized alloys have a combination of high strength (800-1000 MPa), high ductility (10-30%), good e1ectrical and thermal conductivity, corrosion resistance, and excellent machinability. Current applications for W and W-Ti inc1ude counterbalances in military aircraft, radiation shields, lighting components, ignition electrode materials, catalysts in the chemical industry, alloying elements for high speed steels, sputter targets in VLSI chip technology...

show abstract