Barium chromate with boron

Many barium aluminosilicate-based compositions will eventually react with the chromium oxide or aluminum oxide scales on the metal interconnect or metal edge rails to form barium chromate or a celsian phase at the interface [6], This can cause a mechanical weakness that is easily delaminated. Also, compositions that contain boron can react over time with water (steam) to produce B2(OH)2 or B(OH)3 gas. This can decompose the glass and greatly limit the lifetime of the seal. Thus many of the new investigations have emphasized low or no boron glass compositions. 

The ratio of oxidizer to fuel can be altered for a given binary mixture to achieve substantial changes in the rate of burning. The fastest burning rate should correspond to an oxidizer/fuel ratio near the stoichiometric point, with neither component present in substantial excess. Data have been published for the barium chromate /boron system. Table 6. 5 gives the bum time and heat output per gram for this system [4]. 

It has been involved in many industrial explosions. Explodes on contact with aluminum + barium nitrate + potassium nitrate + water. Forms explosive mixtures with aluminum powder + titanium dioxide, ethylene glycol (240°C), cotton lint (245°C), furfural (270°C), lactose, metal powders (e.g., aluminum, iron, magnesium, molybdenum, nickel, tantalum, titanium), sulfur, titanium hydride. Reaction with ethanol + heat forms the explosive ethyl perchlorate. Violent reaction or ignition under the proper conditions with aluminum + aluminum fluoride, barium chromate + mngsten or titanium, boron + magnesium + silicone rubber, ferrocenium diammine-tetrakis(thiocyanato-N) chromate(l —), potassium hexacyanocobaltate(3—), A1 +... 

Heat Values of Boron or Zirconium with Barium Chromate... 

In a series of experiments and measurements performed in the writer s laboratory, it was shown that the range of heat outputs can be vastly extended by using strontium and (even better) calcium chromate in lieu of the barium chromate (Table 23). Because of the lower equivalent weight of the alkaline earth ballast in the calcium chromate, the peak calories per gram for series of mixtures with boron... 

A gasless mixture that is relatively safe to process and to handle. It will burn under greatly diminished atmospheric pressure. Used with NC binder and added powdered glass, it adheres to the substratum and its ash continues to adhere for efficient fire transfer. Its efficacy can be increased by an increase in the percentage of boron and replacement of barium chromate by calcium chromate. 

BENSULFOID (7704-34-9) Combustible solid (flash point 405°F/207°C). Finely divided dry materia forms explosive mixture with air. The vapor reacts violently with lithium carbide. Reacts violently with many substances, including strong oxidizers, aluminum powders, boron, bromine pentafluoride, bromine trifluoride, calcium hypochlorite, carbides, cesium, chlorates, chlorine dioxide, chlorine trifluoride, chromic acid, chromyl chloride, dichlorine oxide, diethylzinc, fluorine, halogen compounds, hexalithium disilicide, lampblack, lead chlorite, lead dioxide, lithium, powdered nickel, nickel catalysis, red phosphorus, phosphorus trioxide, potassium, potassium chlorite, potassium iodate, potassium peroxoferrate, rubidium acetylide, ruthenium tetraoxide, sodium, sodium chlorite, sodium peroxide, tin, uranium, zinc, zinc(II) nitrate, hexahydrate. Forms heat-, friction-, impact-, and shock-sensitive explosive or pyrophoric mixtures with ammonia, ammonium nitrate, barium bromate, bromates, calcium carbide, charcoal, hydrocarbons, iodates, iodine pentafluoride, iodine penloxide, iron, lead chromate, mercurous oxide, mercury nitrate, mercury oxide, nitryl fluoride, nitrogen dioxide, inorganic perchlorates, potassium bromate, potassium nitride, potassium perchlorate, silver nitrate, sodium hydride, sulfur dichloride. Incompatible with barium carbide, calcium, calcium carbide, calcium phosphide, chromates, chromic acid, chromic... 

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