The modes of combustion of copper nanopowders

This article presents the results of experiments on the synthesis of carbon nanofibers by thermal chemical vapor deposition using copper nanopowders obtained by electric explosion of wire as catalysts. Stable growth of carbon nanofibers was carried out at temperatures significantly lower than normally used. The process parameters that are optimal for low-temperature growth of carbon nanofibers have been identified during the performed experiments. The synthesized samples have different diameters and morphology (from spiral to direct). Copper clusters are both at the ends and inside the fibers. The results of IR spectroscopy indicate that the structure of the obtained carbon nanofibers is polymeric. X-ray analysis revealed the presence of a halo on the diffraction patterns at small values of the angle 2θ, which proves that the grown structures have an amorphous nature. There are no groups that are responsible for long-range order in all Raman spectra. Studies by transmission electron microscopy showed that nanostructures do not have an internal channel and nanofibers are solid.

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Flame synthesis of mixed tin-silver-copper nanopowders and conductive coatings

AIChE Journal ◽

10.1002/aic.15132 ◽

2015 ◽

Vol 62 (2) ◽

pp. 408-414 ◽

Cited By ~ 2

Author(s):

Munish K. Sharma ◽

Di Qi ◽

Raymond D. Buchner ◽

Mark T. Swihart ◽

William J. Scharmach ◽

...

Keyword(s):

Flame Synthesis ◽

Conductive Coatings ◽

Silver Copper ◽

Tin Silver Copper ◽

Copper Nanopowders

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Understanding Solidification Kinetics and Microstructural Development of a Lead-Free Composite Solder

Heat Transfer, Volume 1 ◽

10.1115/imece2003-42544 ◽

2003 ◽

Author(s):

D. C. Lin ◽

C. Y. Kuo ◽

T. S. Srivatsan ◽

G.-X. Wang

Keyword(s):

Intermetallic Compound ◽

Cooling Rate ◽

Composite Solder ◽

Microstructural Development ◽

Solidification Temperature ◽

Solidification Kinetics ◽

Copper Powders ◽

Joint Properties ◽

Average Size ◽

Copper Nanopowders

This paper presents and discusses the solidification of Sn-Ag eutectic solder and the effect of cooling rate on its microstructure formation with and without addition of nanosized copper powders. The composite solder mixture was mechanically mixed, and subsequently melted in an aluminum crucible placed in a temperature-controlled furnance, prior to promoting solidification. For all cases significant undercooling of the melt was observed prior to solidification. A reduction in the solidification temperature occurred by the addition of copper nanopowders. Optical microscopy observations revealed the microstructure of solders, in the as-solidified condition, to be appreciably altered by the addition of nanosized copper powders. The copper nanopowders were precipitated as an intermetallic compound. The average size of the intermetallic compound decreased as the cooling rate increased. These results suggest that adding nanosize metallic powders may significantly alter and/or improve solder joint properties.

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Compressibility of hierarchic-architectured agglomerates of hydrogen-reduced copper nanopowders

Journal of Materials Science ◽

10.1007/s10853-015-9414-1 ◽

2015 ◽

Vol 51 (1) ◽

pp. 82-95 ◽

Cited By ~ 3

Author(s):

Dong-Hyun Ahn ◽

Wooyeol Kim ◽

Eun Yoo Yoon ◽

Hyoung Seop Kim

Keyword(s):

Copper Nanopowders

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Investigation of Dependence between Thermal Stability for Nano-Dispersed Metals and Velocity of Flame Spreading and Time Storage

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.682.357 ◽

2014 ◽

Vol 682 ◽

pp. 357-362 ◽

Cited By ~ 2

Author(s):

Yulia A. Amelkovich ◽

Olga B. Nazarenko ◽

Alexander I. Sechin ◽

Kristina O. Fraynova

Keyword(s):

Thermal Stability ◽

Storage Time ◽

Electrical Explosion ◽

Metal Powders ◽

Flame Spreading ◽

Long Time ◽

Thermal Stability Of ◽

Time Lead ◽

Selection Of ◽

Copper Nanopowders

Thermal stability of aluminum, iron and copper nanopowders, produced by electrical explosion of wire during heating in the air, was investigated in the work. Thermal analysis method was used for control of thermal stability for nanodispersed metals in heating in the air. It was shown, that after a long time of storage in air electrical explosion metal nanopowders have had extra active ones. Estimation of velocity of flame spreading in poured layer of the powders was carried out. Quality changes in investigated samples, happened for storage time, lead to increase of flame front length and its line velocity. The results of the researches could be used for diagnostics of fire danger of nanodispersed metals, also for selection of working regimes and provision of fire explosion safety for technologies which produce and apply of nanodispersed metal powders. Time-factor have not effected on criteria concerning the danger of the loads and have not changed its marking.

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