Tantalum combustion

It should be noted that 5-TaN(,ui, has never been produced by conventional methods. We were the first who synthesized it by tantalum combustion in liquid nitrogen [56]. Its structure was investigated by Shekhtman using X-ray... 

Dry chlorine reacts with most metals combustively depending on temperature alurninum, arsenic, gold, mercury, selenium, teUerium, and tin react with dry CI2 in gaseous or Hquid form at ordinary temperatures carbon steel ignites at about 250°C depending on the physical shape and titanium reacts violendy with dry chlorine. Wet chlorine is very reactive because of the hydrochloric acid and hypochlorous acid (see eq. 37). Metals stable to wet chlorine include platinum, silver, tantalum, and titanium. Tantalum is the most stable to both dry and wet chlorine. 

Barium oxide, barium salicylate and/or other organobarium salts 2) Organometallic salts of lanthanum, hafnium and tantalum and their oxides Replacements for lead and copper compounds currently employed for ballistic modification. Particularly attractive due to production of considerably less smoke during combustion of propellants [245]. 

In contrast, the combustion temperatures recorded for the tantalum-nitrogen and niobium-nitrogen systems were much lower than the melting points of the respective metals. Photographs of the cross-sections of undiluted samples do not indicate any macroscopic effect of melting, and neither do SEM photographs of the products. 

Figure 12.9 Tantalum-nitrogen system Effect of nitrogen pressure and solid phase dilution on combustion temperature. Particle size 85 pm.

The combustion of tantalum in nitrogen was studied in detail by Borovinskaya et al.10 Experimental measurements of the propagation characteristics were reported and the various nitrides of tantalum were synthesized under appropriate conditions. The study also showed the use of the chemical furnace technique for the preparation of high-temperature metastable phases. 

Ta20B (c). The data of Moose and Parr1 yield 499.6 for the heat of combustion of tantalum to form Ta205 (c) Muthmann, Weiss, and Riedebauch1 reported 308. 

Group 1 Relatively high benzaldehyde production and relatively low combustion oxides of tantalum, tungsten, zirconium and molybdenum. 

Tantalum-carbon, tantalum-boron, and niobium-boron mixtures may be classified as so-called solid flame systems, where T c is lower than the melting points of both reactants and products. Consequently, the sizes of reactant particles are not expected to change in the combustion wave. The dependence of U on the average metal particle size for these systems is presented in Fig. 47. 

Agrafiotis, C. C Puszynski, J. A., and Hlavacek, V., Experimental study on the synthesis of titanium and tantalum nitrides in the self-propagating regime. Combust. Sci. Tech., 76, 187 (1991). 

Borovinskaya, I. P, Merzhanov, A. G., Pityulin, A. N., and Shehtman, V. S., Self-propagating high-temperature synthesis of the tantalum nitride. In Combustion Processes in Chemical Engineering and Metallurgy (Russ.). (A. G. Merzhanov, ed.). USSR Academy of Science, Chemogolovka, Russia, 1975a, p. 113,... 

Shkiro, V. M., Nersisyan, G. A., and Borovinskaya, 1. R, Principles of combustion of tantalum-carbon mixtures. Combust. Explos. Shock Waves, 14,455 (1978). 

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