aids for technological processes in construction and manufacturing often involve the use of chemical compounds.These include thermite mixture and which have a plurality of formulations.As a result of the use of such compounds, or the user receives a high thermal effect (in welding), or the effect of detonation devices (pyrotechnics incendiary systems).Ingredients for thermite mixture mainly represented by metal elements, but there are other chemical components.The exact composition of the mixture is determined by the application conditions and the effect you want to get.Anyway, the production is carried out termites and not a specialist at home.
General and composition
Chemical termites belong to the group of unitary fuel in uniform proportions containing combustible components and an oxidizer.The specifics of such a mixture causes its ability to ignite, even without access to the air.The characteristics and properties of the thermite mixture is allowed to put it on a par with Bickford fuse and gunpowder.Homogenous compositions may be manufactured in a gaseous form.For this purpose, a suitable combination of gas and air.Such substances include higher requirements for the operation and maintenance, as they have a significant explosion hazard.
Application
Depending on the desired result and the conditions of use termites can provide functions such as thermal effects and pyrotechnics.Pyrotechnic compositions may be used as a means of lighting and in the production of the signal lights.But the main direction of the practical use of termites - is welding.The resulting effects of compounds are distinguished heat resistance and durability.
The principle of thermite mixture during the formation of stitches is melting the composition of the metal components, which provides reliable anti-corrosion compound.But it is important to consider that privarochnaya system required for thermal welding on pipelines, provides not only the copper termosmes but crucible shape with ignition.
traditional composition
In the classical representation of chemical thermodynamics - a mixture of finely divided iron oxide component and aluminum.Such formulations are most in demand in the construction operations (typically welding) and industry.This is due to the fact that the activation mixture by igniting accompanied by fever and the active heat release.Although thermite mixture of iron is better known as ferrumnaya a key role in her action game aluminum.In particular, the process determines the efficiency aluminothermy reactions that make possible welding of steel structures.
pyrotechnic composition
basis of such compositions as a fuel and an oxidant, but in a more complex form.For used components include potassium chlorate (the bulk of the composition), strontium carbonate (about a quarter) and sulfur, coloring the flame.It performs the function of the oxidant potassium chlorate and sulfur acts as the fuel element.In the process of burning thermite pyrotechnic mixture also actively generates heat and the temperature rises: smoke compositions provide hundreds of degrees, and lighting reach 3000 ° C.As a rule, pyrotechnic mixtures are not used for heat exposure, their combustion is accompanied by the formation of a rather intense flame.
Brass mixture
termites, of which consists of copper oxide, are usually made specifically for maintenance welding operations on steel pipelines.High responsibility formed joints necessitated increasing the volume of heat energy released.For this reason, copper thermite mixture comprises ferrosilicon instead ferromanganese, which has not so high melting point.In finished form the composition of this mixture comprises:
- copper oxide - 70%;
- copper powder - 12%;
- aluminum - 10%;
- ferrosilicon (or ferro) - 8%.
This combination of elements improves the quality and reliability of welding by increasing the allocated volumes of thermal energy during the melt.
thermite pencil
The composition of temperature indicating crayon can repeat any of the recipes mix, but its main feature is the cylindrical shape in which the active filling: cable burning and flammable items.It is placed in a crucible shape, made of heat-resistant graphite.End of the cord is displayed in a special hole lid linking part thermite mixture cylinder and ignition means in the form of a match.
in the combustion process when welding on flammable element will be activated thermal mixture pressed into a pencil.Thus, burning termosmesi lead to the fact that heated metal is melted from the surface of the filling tube and forms a solid compound.The advantages of the temperature indicating crayon are two points.Firstly, there is no need to prepare a special anywhere matches.Second, forming the mixture itself in the finished proportions provides ease its storage and transportation.
Termite own hands
To produce simple recipes at home termite need two ingredients - iron oxide and aluminum metal.They should be taken in pyrophoric (mist) form - in this state of matter resemble fine dust.Depending on the order in which volumes should be obtained thermite with their hands, and preparing special dishes - after all operations of preparation, you can use a vessel of aluminum or steel.
By weight proportions of ingredients are as follows: 4 pieces of aluminum to the 3rd scale shares.The components are thoroughly mixed.Further, it is useful to add to the mixture of magnesia (burning potassium permanganate), which performs the function of a catalyst.It can add to the amount of not more than 20% of the total weight of metal compounds.The formulation is then stirred again.
As you can see, the answer to the question of how to make thermite, is quite simple.But it is important to provide a method and its application.Ready composition can be placed in a vessel.It mixture is subjected to a thorough pressing, sealed and sealed to eliminate moisture.After this should be done to the elongated hole of the magnesium strip which enters into the container to a few centimeters.To activate the composition is sufficient to ignite the tape match.
Recipe cast termite
This is one of the most convenient in the preparation of compositions.It can be made and formed into any container.To cast a mixture of differences relates the minimum allocation, but instead the output is slag, a long time withstand moisture.Cast thermite their hands made of the following components: iron oxide (fraction 3), gypsum (2 parts), aluminum powder in a mixture of coarse and fine metals.All components are mixed and then to soften the gypsum is added water.The resulting mass is molded, and in this form it is necessary to leave a half-hour.The mixture was again filled with water and stored for drying for one week.When that time passes, preferably in the sun again dry up, and then drill a hole for activating the charge.
