Saturday, December 12, 2009

Thermite

Thermite always interested me. One unit had a class where we got to destroy radio equipment, fixed installation, with thermite grenades and it was cool to see a radio rack reduced to a pool of certainly inoperable and much molten metals.

Thermite is a pyrotechnic composition of a metal powder and a metal oxide, which produces an aluminothermic reaction known as a thermite reaction. It is not explosive, but can create short bursts of extremely high temperatures focused on a very small area for a short period of time.

Thermites can be a diverse class of compositions. The fuels are often aluminium, magnesium, calcium, titanium, zinc, silicon, and boron. The oxidizers can be boron oxide, silicon oxide, chromium oxide, manganese oxide, iron oxide, iron oxide, copper oxide, and lead oxide.

The most common thermite is aluminium-iron oxide. Ignition of a thermite reaction normally requires only a simple child's sparkler or easily obtainable magnesium ribbon, but may require persistent efforts, as ignition can be unreliable and unpredictable. Thermite reactions require very high temperatures for initiation.

Thermite hand grenades and charges are typically used by armed forces in both an anti-materiel role and in the partial destruction of equipment, the latter being common when time is not available for safer or more thorough methods. Because standard iron-thermite is difficult to ignite, burns with practically no flame and has a small radius of action, standard thermite is rarely used on its own as an incendiary composition. It is more usually employed with other ingredients added to enhance its incendiary effects. Thermate-TH3 is a mixture of thermite and pyrotechnic additives which have been found to be superior to standard thermite for incendiary purposes. Its composition by weight is generally 68.7% thermite, 29.0% barium nitrate, 2.0% sulfur and 0.3% binder (such as PBAN). The addition of barium nitrate to thermite increases its thermal effect, produces a larger flame, and significantly reduces the ignition temperature. Although the primary purpose of Thermate-TH3 by the armed forces is as an incendiary anti-materiel weapon, it also has uses in welding metal components.

A classic military use for thermite is disabling artillery pieces, and has been used commonly for this purpose since the Second World War. Thermite can permanently disable artillery pieces without the use of explosive charges and therefore can be used when silence is necessary to an operation. There are several ways to do this. By far the most destructive method is to weld the weapon shut by inserting one or more armed thermite grenades into the breech and then quickly closing it. This makes the weapon impossible to load. An alternative method is to insert an armed thermite grenade down the muzzle of the artillery piece, fouling the barrel. This makes the piece very dangerous to fire. Yet another method is to use thermite to weld the traversing and elevation mechanism of the weapon, making it impossible to aim properly.

Thermite was also used in both German and Allied incendiary bombs during World War II. Incendiary bombs usually consisted of dozens of thin thermite-filled canisters (bomblets) ignited by a magnesium fuse. Incendiary bombs destroyed entire cities due to the raging fires that resulted from their use. Cities that primarily consisted of wooden buildings were especially susceptible. These incendiary bombs were utilized primarily during night time air raids. Bomb sights could not be used at night, creating the need to use munitions that could destroy targets without the need for precision placement.

One should take the following with a grain of salt (not literally). Provided for entertainment purposes only.
Obtaining the Aluminum
1) Go to a machine shop. They will usually give you aluminum powder for sweeping the floor or something.
2) Break open an Etch-A-Sketch, the stuff inside is pure aluminum powder.
3) Go to a paint store, they usually have powdered aluminum that people use to mix into paints to give it pigment.
4) Get a grinder, and something made of aluminum. Good ideas are soda cans, bike frames, and lacrosse sticks. Start grinding the aluminum and collect the sparks in a container.
5) Search eBay, they sell it for pretty cheap.

Obtaining the Iron Oxide (Rust)
1) Take some steel wool then put it in a jar and then cover it wool with water. Use a magnet to make sure the steel wool doesn't float during the reaction process. Next, put in 5 tablespoons of regular bleach into the water and 5 tablespoons of regular vinegar. Wait a day or so and then filter the brown paste with a coffee filter. Leave it out to dry overnight.
2) Go to a paint store, they usually have powdered iron oxide that people use to mix into paints to give it pigment.
3) Connect wires to a direct current (9-volt battery), strip both ends and put them into a saltwater solution. Let them sit for five minutes. One of them will start bubbling more than the other. This is the POSITIVE(+) wire. Put a nail tied to the positive wire into the jar. Now put the negative wire in the other end. Now let it sit overnight and in the morning scrape the rust off of the nail & repeat until you have a bunch of rust on the bottom of the glass. Let it dry out, and crush it into a powder.
4) Search eBay, they sell it for pretty cheap.

Mixing the Stuff
Thermite is 8 grams of iron oxide to 3 grams of aluminum. The formula is by weight but because aluminum is very light, it will appear to be approximately a 50-50 mix. Put them together in a container and mix them until it is an even mixture. If you want, mix four parts thermite with one part clay or Play-Doh and knead thoroughly for moldable thermite.

Igniting
Thermite needs a lot of heat to light, that means magnesium. Find some magnesium ribbon, or a sparkler that contains magnesium and put it into a pile of thermite. Light it with a torch, and run!

I'm gonna repeat myself. You and you alone are responsible for your use of this information. I'm not responsible for anything stupid that you or your children do.

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