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On the Mechanism of Boron IgnitionBoron filaments were electrically heated in air and argon/oxygen mixtures while their resistance, temperature, and radiation at the wavelengths of BO and BO2 bands were monitored. The filaments 'burned' in two distinct stages. Samples of the filaments were quenched at different times before and during the burning and analyzed using electron microscopy. The beginning of the first stage combustion characterized by a local resistance minimum, a sharp spike in boron oxide radiation emission, and a rapid rise in temperature, occurred at 1500 +/- 70 deg. C, independent of pre-heating history and oxygen content (540%) in the gas environment. The data suggest that a phase transition occurs in the filaments at this temperature that triggers stage one combustion. Significant amounts of oxygen were found inside quenched filaments. Large spherical voids formed in the boron filaments during their second stage combustion which is interpreted to indicate a crucial role for the gas dissolution processes in the combustion scenario.
Document ID
19980217992
Acquisition Source
Legacy CDMS
Document Type
Conference Paper
Authors
Keil, D. G.
(AeroChem Research Labs., Inc. Princeton, NJ United States)
Dreizin, E. L.
(AeroChem Research Labs., Inc. Princeton, NJ United States)
Felder, W.
(AeroChem Research Labs., Inc. Princeton, NJ United States)
Vicenzi, E. P.
(Princeton Univ. NJ United States)
Date Acquired
August 18, 2013
Publication Date
October 1, 1997
Publication Information
Publication: 34th JANNAF Combustion Subcommittee Meeting
Volume: 2
Subject Category
Inorganic And Physical Chemistry
Funding Number(s)
CONTRACT_GRANT: NAS3-27259
CONTRACT_GRANT: N00024-96-C-4149
Distribution Limits
Public
Copyright
Work of the US Gov. Public Use Permitted.

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