Special Materials in Pyrotechnics: V. Military Applications of Phosphorus and its Compounds

Abstract

This paper reviews the military applications of phosphorus in obscurants, incendiaries, float and smoke signals, friction igniters and decoys. Whereas white phosphorus (WP) is still in use as both incendiary and obscurant ammunition it has been mainly replaced today by red phosphorus (RP). For part VI see Ref. [1].

Green Primary Explosives

“…White phosphorus has been used in smoke formulations, among other applications, but is highly toxic in both vapor and solid forms and can also spontaneously ignite in air at temperatures of 50°C or less, causing fires that are extremely difficult to extinguish. For these reasons, it is slowly being phased out of practical applications [57]. Red phosphorus, however, has gradually begun to see more attention.…”

“…This reaction can be accelerated at high temperatures and under alkaline conditions, although it is somewhat mitigated by formulating red phosphorus particles with suitable coating agents. Additionally, red phosphorus has led to several unexpected explosions when tested in confined ammunition applications, making it a risky material to work with from a handling perspective [57]. Despite these concerns, red phosphorus has been the subject of several primer inventions.…”

Advances Toward the Development of “Green” Pyrotechnics

“…When kept in water, WP is quite stable and does not ignite. In fact, Koch points out that an old method of filling smoke grenades with WP was by an underwater melt-casting process [77]. As outlined in Eq.…”

Metal–Halocarbon Pyrolant Combustion

“…Propellants and pyrolants on the contrary undergo a thermally propagated reaction and yield either large amount of gaseous species, or in the case of pyrolants yield mainly condensed products. Unlike most high explosives, which are homogeneous organic compounds containing nitro-and nitramine groups, pyrolants and most propellants are heterogeneous fuel/oxidizer mixtures [1,2].The term pyrolant describes hot burning compositions that are constituted from micrometric or nanometric metal powders and crystalline and/or polymeric oxidizers.Typical pyrolants are used as illuminant (Mg/NaNO 3 ), thermite (Al/Bi 2 O 3 ), and igniter (Zr/BaCrO 4 ) compositions [3], in addition coruscative combinations such as, for example, Zn/S or Mg/P [4, 5] find use as both amateur propellants (sic) and incendiaries [6].An important group of pyrolants consists of combinations of metal powders with halocarbon compounds. The large energy content of metal-halocarbon pyrolants stems from the high enthalpy of formation of the corresponding metal-halogen bond (MÀX).…”

“…Typical pyrolants are used as illuminant (Mg/NaNO 3 ), thermite (Al/Bi 2 O 3 ), and igniter (Zr/BaCrO 4 ) compositions [3], in addition coruscative combinations such as, for example, Zn/S or Mg/P [4, 5] find use as both amateur propellants (sic) and incendiaries [6].…”