Thermite material, ignition

For larger sizes, eg, 15.3cm, a shell was designed which contained units of thermite or other incendiary materials held in perforated cases. These units were ignited from a central tube and expelled from the front of the shell by the explosion of the powder charge located in the base... 

Pyrots are mixts of fuels and oxidizers. The ignition and propagation of reaction mechanisms are similar to that discussed for expls and pro-pints. The reaction rate and ability to detonate is dependent on the specific materials involved, their particle size, the intimacy of the mix and confinement. Because some pyrot mixes on reacting produce very little gas, it is very unlikely that detonation could ever be achieved. An example of such a mix is Al/ferric oxide or Thermite. In other, mixes of highly reactive materials, Mg/K chlorate for example, detonation can readily be achieved... 

SDO (Synthetic Drying Oil). A commercial polymer of acetylene (such as SDO-80) which was evaluated as an incendiary mixt component during WWII. A typical mixt contg 1 p of SDO-80 was mixed with 2p of Na nitrate, and the material was exposed to the air with occasional stirring until it had absorbed sufficient oxygen (about 64% of its wt) to form a sticky brown-colored gel. The gel, when ignited, gave a burn time of brief duration and little incendiary value. It was considered to be about 1/10 as effective as a Mg bomb and 1/5 as effective as a gum incendiary mixt of that era. Its performance was comparable to that of thermite Refs 1) L.F. Fieser, OSRD 173 (1941)... 

Sodium was used as a filling for the German 17.5-cm. incendiaiy shell. In that shell, which was the largest incendiary shell used during the war, the sodium was ignited by thermite. Sodium w as also used in some of the spontaneously inflammable liquids of the World Warto ignite the mixturt on contact with water. Except for this latter use, sodium was not aa effective incendiaiy material, as it required considerable moisture to... 

The use of oxidizing combustible mixtures in drop bombs and other relatively large incendiary devices was Jess successful than in small-arms ammunition. Such mixtures were used early in the war in incendiary artillery shell and in drop bombs, but in many cases were later discarded for the thermit -tjT>e mixtures. As a primary incendiary material w houc chief function was to ignite other materials in drop bombs, the following mixture was used ... 

This item consists of a mixture of granulated sugar and potassium chlorate or sodium chlorate. It can be used to ignite all the incendiaries listed in chapter 4 except Thermite (0307). It may be used directly as an incendiary on readfly flammable material such as rags, dry paper, dry hay, or in the combustible vapor above liquid fuels. 

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