ENVIRONMENTALLY FRIENDLY SOLID STATE INCENDIARY MIXTURES

Stefan Kolev, Tzvetomir Tzonev

SURT Technologies LTD, Sofia, Bulgaria; e-mail: info@surt-technologies.com Phone (Stefan Kolev): +359 878 633801

SURT Technologies LTD has developed two types of solid state incendiary mixtures. The

first type is cast cured, polymer bonded mixture, designed to be used against general targets.

The second type is pressed, hybrid mixture, capable to melt and penetrate through steel plates.

Both compositions are environmentally friendly and do not contain heavy metals, fluorides or

phosphorous.

Incendiary mixtures used so far can be grouped into two major categories: 1. Using thickened

petrol (with or without added oxidizers and metals) or 2. Solid state mixtures. Solid state

mixtures can be based on phosphorus (red or white), thermite, or mixtures electron - oxidizer.

The main advantages of mixtures based on petroleum products are easy ignition and the low

price. Their disadvantages are the volatility of the components, a relatively short storage time,

and the low density. Solid-phase mixtures based on phosphorus are widely spread in

incendiary ammunition. Their advantages are the easy ignition and relatively high density.

Solid-state incendiaries allow loading ammunitions, which rotate in flight. Deficiencies of

phosphorus munitions are - first the toxicity of white phosphorus, which requires its

replacement with red. Red phosphorus itself is less effective as incendiary agent. Another

major disadvantage of phosphorous munitions is the danger of premature ignition if accidental

failure of the container occurs. Thermite munitions have a very high combustion temperature,

but they cannot achieve the desired area of impact. Mixtures of electron- oxidizer type,

especially in thin shell of electron (Mg-Al alloy) generally have very good parameters. The

content of magnesium in the alloy, however, makes them expensive, dangerous and difficult

to store.

Polymer bonded incendiary mixture

Based on previous experience and test results, SURT Technologies LTD has developed a

polymer bounded incendiary mixture with improved characteristics, Figure 1.

Figure 1. Laboratory sample of the incendiary mixture. Polymer bonded incendiary mixture has the next characteristics:

1. Price – not higher than 20 USD/kg. All needed materials are multi ton products of the

chemical industry.

2. Temperature of burning higher than 800oC (Figure 3), stable combustion under water

(Figure 2) and sand.

3. Temperature stability from -60 to + 120oC. Temperature stability up to 250oC for more than

an hour.

4. Lack of any hygroscopic, volatile, and highly toxic materials for the preparation of the

mixture. It does not contain phosphorus, magnesium, or heavy metals. The incendiary mixture

does not contain any petroleum products. The products of combustion are 100%

environmentally friendly.

6. Cast-cure technology, well studied and adopted worldwide. High mechanical properties,

Shore A hardness = 50.

7. Ability to be stored within at least 10 years from the date of manufacture.

Figure 2. Burning of 12 grams of the incendiary mixture under water. Overheated hydrogen

and other gasses, formed by the reaction of the ignited mixture and water, burn on top.

Figure 3. Aluminum plate burned and Beher glass melted by the mixture.

Figure 4. Burning of 1 kg solid-state incendiary mixture in a wooden ammo box. The incendiary mixture can be used on a whole variety of targets including buildings,

vehicles, starting fires in open grounds. The mixture ignites fabric, plastic, wood and melts

aluminum. Tested on wooden target, 1000 grams of the incendiary mixture, cast in thin walled

aluminum container, was ignited in a wooden box, Figure 4. Time of burning was 25 seconds

(speed of burning about 1 cm/s). As a result, the box ignited and burned completely.

In a further test a 4 kg incendiary mixture charge, designed to spread and ignite the mix, was

initiated inside a van, Figure 5. Needless to say it was a massive overkill, the van burned

completely and mixture was dispersed out of it.

The incendiary mixture could be loaded in practically every type of ammunition, from 12.7

mm bullets to multi ton aviation bombs. It is extremely well suited for penetration rounds that

will deliver the mixture inside structures or vehicles before ignition.

Figure 5. Results from the action of 4 kg mixture on a van. Hybrid mixture

In addition to the polymer bonded incendiary, SURT Tech. LTD has developed a modern

hybrid mixture that is loaded into munitions by pressing. It is absolutely environmentally

friendly, contains no heavy metals (unlike TH-3), and has effectiveness higher than that of

TH-3 thermite. The speed of burning is controlled by a catalytic mechanism and layering of

the charges. It can therefore be tuned, according to the client’s request, from a few seconds to

a few minutes for 100 g charges. This type of incendiary mix allows for unprecedented

versatility and control of variables – speed of burning and scattering of solid residue. The

hybrid mixture can be loaded in any existing weapon system with caliber higher than 30 mm.

It is very suitable for hand grenades where it can be used to start fire in combustible materials

or melt through at least 4 mm steel plate (500 g charge), Figure 6-9. It can also be used to

disable artillery pieces by welding the breach or depositing molten metal into the barrel. This

incendiary mixture is also suitable for 40 mm under barrel grenades, where its effectiveness is

still very high, it ignites any combustible material and melts through at least 2 mm steel plate

(50-100 g charge).

Hybrid incendiary mixture has the next characteristics:

1. Price – not higher than 20 USD/kg. All needed materials are multi ton products of the

chemical industry.

2. Temperature of burning higher than 2000oC, stable combustion under water and sand.

3. Temperature stability from -60 to + 120oC. Temperature stability up to 250oC for more than

an hour.

4. Lack of any hygroscopic, volatile, and highly toxic materials for the preparation of the

mixture. It does not contain phosphorus, magnesium, or heavy metals. The incendiary mixture

does not contain any petroleum products. The products of combustion are 100%

environmentally friendly.

6. Pressed technology, well studied and adopted worldwide. High mechanical properties,

Shore A hardness > 70.

7. Ability to be stored within at least 10 years from the date of manufacture.

Figure 6. Incendiary grenade, filled with the hybrid mixture (500 g) in place, target is 4 mm

steel plate.

Figure 7. Thickness of the plate used in the experiment.

Figure 8. Ignition of the grenade (top), and molten metal leaking through the plate (bottom).

Figure 9. Results from both sides, steel plate is 4 mm thick.