The use and composition of the thermite mixture

Auxiliary means for providing technological processes in construction and production often involve the use of chemical compounds. These include the term mixtures, which have many formulations. As a result of using such formulations, the user receives either increased thermal effect (in welding operations), or the detonation mechanism effect (in incendiary pyrotechnic systems). Ingredients for the thermite mixture are mainly represented by metal elements, but other chemical components are also found. The exact composition is determined by the application conditions of the mixture and the effect to be obtained. Anyway, the production of termites is made and not by a specialist at home.

General information and composition

Chemical termites belong to the unitary fuel group, in uniform proportions containing combustible components and oxidizer. The specificity of this mixture causes its ability to ignite even without access to air. The characteristics and properties of the thermite mixture allow it to be placed on a par with the Bickford cord and gunpowder. Homogeneous compounds can be produced in a gaseous form. For this, a combination of suitable gas and air is used. Such substances provide for higher requirements for operating conditions and content, since they have a significant explosive hazard.

Application

Depending on the desired result and conditions of use, termites can provide such functions as thermal impact and pyrotechnic effect. Pyrotechnic compounds can be used as lighting equipment and in the production of signal lights. But the main direction of practical use of termites is welding. The compounds obtained as a result of the action of thermal energy differ in strength and durability.

The principle of the termite mixture during the formation of seams is the melting of the composition of metal components, which provides a reliable corrosion protection. But it is important to take into account that the welding system required for thermal welding on pipelines provides not only a copper thermosubstance, but also a crucible with ignition.

Traditional composition

In the classical view, chemical termite is a mixture of finely divided components of iron scale and aluminum. It is these compounds that are most in demand in construction operations (usually welding) and industry. This is due to the fact that the activation of the mixture by ignition is accompanied by an increase in temperature and an active release of heat. Although the termite iron mixture is more commonly known as ferrous, the key role in its operation is played by aluminum. In particular, the process of aluminothermy determines the effectiveness of reactions, thanks to which it is possible to weld steel structures.

Pyrotechnic composition

The basis of such compositions is also fuel and oxidizer, but in a complicated form. The components used include potassium chlorate (the main part of the composition), strontium carbonate (about a quarter) and sulfur that stains the flame. The oxidizing agent is performed by potassium chlorate, and sulfur acts as a combustible element. In the process of burning the pyrotechnic thermite mixture, heat is also actively released and the temperature rises: the smoke compositions provide hundreds of degrees, and the lighting compositions reach 3,000 ° C. As a rule, pyrotechnic mixtures are not used to provide thermal effects, their combustion is accompanied by a rather intense formation of a flame.

Copper mixtures

Termites, in which copper oxide is present, are usually made purposefully for servicing welding operations on steel pipelines. The high responsibility of the welds formed necessitated an increase in the amount of heat released. For this reason, the termite copper mixture includes ferrosilicon instead of ferromanganese, which has a not so high melting point. In the finished form, the composition of such a mixture includes:

• Copper oxide - 70%;
• Copper powder - 12%;
• Aluminum - 10%;
• Ferrosilicon (or ferromanganese) - 8%.

This combination of elements improves the quality and reliability of welding operations due to an increase in the heat energy released during the melt process.

Termite pencil

In its composition, the thermocannette can repeat any of the recipes of the mixture, but its main feature is the cylindrical shape in which the active filling is located: the burning cord and the flammable elements. It is placed in a crucible mold made of heat-resistant graphite. The end of the cord is removed into the special opening of the cover, connecting the composition of the thermite mixture of the cylinder and the ignition means in the form of a match.

In the process of combustion, when welding on a flammable element, activation of a thermal mixture pressed into a pencil will occur. Thus, the burning out of the thermal mix will result in the heated metallic filling melting with the surface of the pipe and forming a strong connection. The merits of thermal pencils are two points. First, there is no need to prepare a special thermos. Secondly, the very molding of the mixture in finished proportions ensures the convenience of its storage and transportation.

Termits with own hands

To make a simple termite formulation at home, you will need two ingredients - iron scale and aluminum metal. They should be taken in pyrophoric (finely dispersed) form - in this state the substances resemble fine dust. Depending on the volume in which the termite mixture must be obtained by hand, special dishes are also prepared - after all the operations, a vessel made of aluminum or steel can be used.

By weight, the proportions of the ingredients will be as follows: 4 parts of aluminum to 3 parts of scale. The components are thoroughly mixed. Further, it will not be superfluous to add to the mixture of magnesia (burnt manganese), which will fulfill the function of the catalyst. It can be introduced in a volume that is not more than 20% of the total mass of metallic substances. Then the composition is again mixed.

Apparently, the answer to the question of how to make a thermite mixture is quite simple. But it is important to provide and the way it is used. The finished composition can be placed in a vessel. In it, the mixture is subjected to thorough pressing, compacted and clogged to prevent moisture penetration. After this, you should make an oblong hole for the magnesium tape, which will enter the container a few centimeters. To activate the composition, it is enough to set the tape on fire with a match.

Recipe for cast termite

This is one of the most convenient formulations. It can be made and molded in any container. The difference in the cast mixture is the minimum separation, but instead of this, there is a slag leaving the moisture for a long time. The cast thermite mixture with its own hands is made of the following components: iron oxide (3 parts), gypsum (2 parts), aluminum powder in the form of a mixture of coarse and fine metals. All components are mixed, and then water is added to soften the gypsum. The resulting mass is molded, and in this form it must be left for half an hour. The mixture is then refilled with water and stored for drying for a week. When this time passes, it is advisable to dry the compound once more in the sun, and then drill a hole for the activating charge.