The concept and types of explosives. Liquid explosives Like explosives

Terminology

The complexity and diversity of the chemistry and technology of explosives, political and military contradictions in the world, the desire to classify any information in this area have led to unstable and diverse formulations of terms.

Industrial Application

Explosives are also widely used in industry for the production of various blasting operations. The annual consumption of explosives in countries with developed industrial production, even in peacetime, is hundreds of thousands of tons. AT war time the consumption of explosives increases sharply. So, during the 1st World War in the warring countries it amounted to about 5 million tons, and in the 2nd World War it exceeded 10 million tons. The annual use of explosives in the United States in the 1990s was about 2 million tons.

• throwing
  Throwing explosives (gunpowder and rocket propellants) serve as sources of energy for throwing bodies (shells, mines, bullets, etc.) or propelling rockets. Their distinctive feature is the ability to explosive transformation in the form of rapid combustion, but without detonation.
• pyrotechnic
  Pyrotechnic compositions are used to obtain pyrotechnic effects (light, smoke, incendiary, sound, etc.). The main type of explosive transformations of pyrotechnic compositions is combustion.

Throwing explosives (gunpowder) are mainly used as propellant charges for various types of weapons and are intended to give a projectile (torpedo, bullet, etc.) a certain initial speed. Their predominant type of chemical transformation is rapid combustion caused by a beam of fire from the means of ignition. Gunpowder is divided into two groups:

a) smoky

b) smokeless.

Representatives of the first group can serve as black powder, which is a mixture of saltpeter, sulfur and coal, such as artillery and gunpowder, consisting of 75% potassium nitrate, 10% sulfur and 15% coal. The flash point of black powder is 290 - 310 ° C.

The second group includes pyroxylin, nitroglycerin, diglycol and other gunpowders. The flash point of smokeless powders is 180 - 210 ° C.

Pyrotechnic compositions (incendiary, lighting, signal and tracer) used to equip special ammunition are mechanical mixtures of oxidizers and combustible substances. Under normal conditions of use, when burned, they give the corresponding pyrotechnic effect (incendiary, lighting, etc.). Many of these compounds also have explosive properties and under certain conditions can detonate.

According to the method of preparation of charges

• pressed
• cast (explosive alloys)
• patronized

By areas of application

• military
• industrial

• for mining (mining, production of building materials, stripping)
  Industrial explosives for mining according to the conditions of safe use are divided into

• non-safety
• safety

• for construction (dams, canals, pits, road cuts and embankments)
• for seismic exploration
• for the destruction of building structures
• for material processing (explosion welding, explosion hardening, explosion cutting)

• special purpose (for example, means of undocking spacecraft)
• anti-social use (terrorism, hooliganism), often using low-quality substances and artisanal mixtures.
• experimental.

According to the degree of danger

There are various systems for classifying explosives according to the degree of danger. The most famous:

• Globally Harmonized System of Classification and Labeling of Chemicals

• Classification according to the degree of danger in mining;

By itself, the energy of the explosive is small. An explosion of 1 kg of TNT releases 6-8 times less energy than the combustion of 1 kg of coal, but this energy is released during an explosion tens of millions of times faster than during conventional combustion processes. In addition, coal does not contain an oxidizing agent.

see also

Literature

1. Soviet military encyclopedia. M., 1978.
2. Pozdnyakov Z. G., Rossi B. D. Handbook of Industrial Explosives and Explosives. - M.: "Nedra", 1977. - 253 p.
3. Fedoroff, Basil T. et al Enciclopedia of Explosives and Related Items, vol.1-7. - Dover, New Jersey: Picatinny Arsenal, 1960-1975.

Links

• // Encyclopedic Dictionary of Brockhaus and Efron: In 86 volumes (82 volumes and 4 additional). - St. Petersburg. , 1890-1907.

Wikimedia Foundation. 2010 .

• New Wave (series)
• Rucker, Rudy

See what "Explosives" is in other dictionaries:

Explosives- (a. explosives, blasting agents; n. Sprengstoffe; f. explosifs; i. explosivos) chem. compounds or mixtures of substances capable, under certain conditions, of extremely fast (explosive) self-propagating chem. transformation with the release of heat ... Geological Encyclopedia

EXPLOSIVES- (Explosive matter) substances that are capable of giving the phenomenon of an explosion due to their chemical transformation into gases or vapors. V. V. are divided into propelling gunpowder, blasting having a crushing effect and initiating to ignite and detonate others ... Marine Dictionary

EXPLOSIVES- EXPLOSIVES, a substance that quickly and sharply reacts to certain conditions, with the release of heat, light, sound and shock waves. Chemical explosives for the most part are compounds with a high content ... Scientific and technical encyclopedic dictionary

Since the invention of gunpowder, the world race for the most powerful explosives has not stopped. This is true even today, despite the appearance of nuclear weapons.

Hexogen is an explosive drug

Back in 1899, for the treatment of inflammation in the urinary tract, the German chemist Hans Genning patented the drug hexogen, an analogue of the well-known hexamine. But soon the doctors lost interest in him due to side intoxication. Only thirty years later it became clear that hexogen turned out to be the most powerful explosive, moreover, more destructive than TNT. A kilogram RDX explosive will produce the same destruction as 1.25 kilograms of TNT.

Specialists in pyrotechnics mainly characterize explosives by explosiveness and brisance. In the first case, one speaks of the volume of gas released during the explosion. Like, the larger it is, the more powerful the explosiveness. Brisance, in turn, depends already on the rate of formation of gases and shows how explosives can crush surrounding materials.

10 grams of RDX release 480 cubic centimeters of gas during an explosion, while TNT - 285 cubic centimeters. In other words, hexagen is 1.7 times more powerful than TNT in explosiveness and 1.26 times more dynamic in blasting.

However, the media most often uses a certain average indicator. For example, the atomic charge "Baby", dropped on August 6, 1945 on the Japanese city of Hiroshima, is estimated at 13-18 kilotons of TNT. Meanwhile, this does not characterize the power of the explosion, but indicates how much TNT is needed to release the same amount of heat as during the indicated nuclear bombardment.

HMX - half a billion dollars for air

In 1942, the American chemist Bachmann, while conducting experiments with RDX, accidentally discovered a new substance, HMX, in the form of an impurity. He offered his find to the military, but they refused. Meanwhile, a few years later, after it was possible to stabilize the properties of this chemical compound, the Pentagon nevertheless became interested in HMX. True, it was not widely used in its pure form for military purposes, most often in a casting mixture with TNT. This explosive was called "Octolome". It turned out to be 15% more powerful than hexogen. With regard to its effectiveness, it is believed that one kilogram of HMX will produce as much destruction as four kilograms of TNT.

However, in those years, the production of HMX was 10 times more expensive than the production of RDX, which hindered its production in the Soviet Union. Our generals have calculated that it is better to produce six shells with hexogen than one with octol. That is why the explosion of an ammunition depot in the Vietnamese Quy Ngon in April 1969 cost the Americans so dearly. Then a Pentagon spokesman said that due to the sabotage of the partisans, the damage amounted to 123 million dollars, or about 0.5 billion dollars in current prices.

In the 80s of the last century, after Soviet chemists, including E.Yu. Orlov, developed an efficient and inexpensive technology for the synthesis of HMX, in large volumes it began to be produced in our country.

Astrolite - good, but smells bad

In the early 60s of the last century, the American company EXCOA presented a new explosive based on hydrazine, claiming that it was 20 times more powerful than TNT. The Pentagon generals who arrived for the test were knocked off their feet by the terrible smell of an abandoned public toilet. However, they were willing to endure it. However, a number of tests with air bombs filled with astrolite A 1-5 showed that the explosive was only twice as powerful as TNT.

After Pentagon officials rejected the bomb, EXCOA engineers suggested new version of this explosive is already under the brand name "ASTRA-PAK", and for digging trenches by the method of directed explosion. In the commercial, a soldier poured water on the ground in a thin stream, and then detonated the liquid from cover. And a man-sized trench was ready. On its own initiative, EXCOA produced 1000 sets of such explosives and sent them to the Vietnamese front.

In reality, everything ended sadly and anecdotally. The resulting trenches exuded such a disgusting smell that American soldiers sought to leave them at any cost, regardless of orders and danger to life. Those who remained lost consciousness. The unused kits were sent back to the EXCOA office at their own expense.

Explosives that kill their own

Along with hexogen and octogen, hard-to-pronounce tetranitropentaerythritol, which is often called PETN, is considered a classic explosive. However, due to its high sensitivity, it has not been widely used. The fact is that for military purposes, it is not so much explosives that are more destructive than others that are important, but those that do not explode from any touch, that is, with low sensitivity.

Americans are especially meticulous about this issue. It was they who developed the NATO standard STANAG 4439 for the sensitivity of explosives that can be used for military purposes. True, this happened after a series of grave incidents, including: the explosion of a warehouse at the American Air Force Base Bien Ho in Vietnam, which cost the lives of 33 technicians; the disaster on board the USS Forrestal, which resulted in damage to 60 aircraft; detonation in the storage of aircraft missiles aboard the aircraft carrier Oriskany (1966), also with numerous casualties.

Chinese destroyer

In the 80s of the last century, the substance tricyclic urea was synthesized. It is believed that the first to receive this explosive were the Chinese. Tests showed the enormous destructive power of "urea" - one kilogram of it replaced twenty-two kilograms of TNT.

Experts agree with such conclusions, since the “Chinese destroyer” has the highest density of all known explosives, and at the same time has the highest oxygen ratio. That is, during the explosion, all material is completely burned. By the way, for TNT it is 0.74.

In reality, tricyclic urea is not suitable for military operations, primarily due to poor hydrolytic stability. The very next day, with standard storage, it turns into mucus. However, the Chinese managed to get another "urea" - dinitrourea, which, although worse in explosiveness than the "destroyer", is also one of the most powerful explosives. Today it is produced by the Americans at their three pilot plants.

Pyromaniac's dream - CL-20

The CL-20 explosive is currently positioned as one of the most powerful. In particular, the media, including Russian ones, claim that one kg of CL-20 causes destruction, which requires 20 kg of TNT.

Interestingly, the Pentagon allocated money for the development of the CL-20 only after the American press reported that such explosives had already been made in the USSR. In particular, one of the reports on this topic was called like this: “Perhaps this substance was developed by the Russians at the Zelinsky Institute.”

In reality, as a promising explosive, the Americans considered another explosive, first obtained in the USSR, namely diaminoazoxyfurazan. Along with high power, which significantly exceeds octogen, it has low sensitivity. The only thing holding back its widespread use is the lack of industrial technology.

Explosive penetration test results: on the right - for a 30-gram HMX charge, on the left - for the same charge of CL-20

The search for ever more powerful explosives has been going on for centuries. Traditional gunpowder has long gone from the scene, but the emergence of compact robotic warfare, including drones, only stimulates new searches. The smaller size and mass of warheads will retain the killing power of their larger predecessors only thanks to the latest achievements of chemists.

The ideal explosive is necessarily a balance between maximum explosive power and maximum stability during storage and transport. This is also the maximum density of chemical energy, the minimum price in production and, preferably, environmental safety. It is not easy to achieve all this, therefore, for developments in this area, they usually take already proven formulas - TNT, RDX, pentrite, hexanitrostilbene, etc. - and try to improve one of the desired characteristics without compromising the rest. Completely new compounds appear extremely rarely.

An interesting exception to this rule may be hexanitrohexaazaisowurtzitane (CL-20), which is poised to enter the elite list of popular explosives. First synthesized in California in 1986 (hence the CL in its abbreviated name), it contains chemical energy in the most dense form. So far, it is industrially produced by a few companies at a price of more than $ 1,300 per kilogram, however, with the transition to large-scale synthesis, the cost may fall, according to experts, by 5-10 times.

Today, one of the most effective military explosives is octogen, which is used in plastic charges and costs in the order of $100 per kilogram. However, the CL-20 (look at the illustration on the left) shows noticeably more power: in tests for penetrating through steel blocks, it is 40% more effective. This power is provided by a higher detonation velocity (9660 m/s versus 9100 m/s) and a higher density of matter (2.04 g/cm3 versus 1.91).

Such incredible strength suggests that the CL-20 will be especially useful for use with compact combat systems, such as modern drones. However, it is dangerously sensitive to impacts and concussions - much like penthrite, the compound most sensitive to them of all the explosives in use. Initially, it was assumed that CL-20 could be used together with a plastic binder (in a ratio of 9: 1), although in parallel with the reduction in the risk of detonation, explosive power is also reduced.

In a word, the history of the CL-20, which began in the 1980s, has not yet turned out too well. However, chemists do not stop experimenting with it. One of them was the American professor Adam Matzger (Adam Matzger), under whose leadership the substance seems to have been improved to an acceptable form. The authors tried to change not the structure, but the form.

Here it is worth saying that if we take a mixture of crystals of two different substances, a separate molecule of each crystal is surrounded by neighbors like it. The properties of the mixture turn out to be something in between the properties of either substance in its pure form. Instead, Matzger and his colleagues tried the method of co-crystallization from a common solution - they managed to obtain molecular crystals containing both substances at the same time: for two molecules of CL-20, there is one molecule of HMX.

After studying the properties of this compound, the scientists found that its detonation speed is 9480 m/s - that is, approximately in the middle between the speeds for pure CL-20 and HMX. On the other hand, the stability is almost as high as that of pure HMX (according to the authors, due to the formation of additional hydrogen bonds between the two types of molecules, which stabilize the sensitive CL-20 molecule). In addition, the crystal density is about 20% higher than that of HMX, which makes it even more efficient. In other words, such a crystal turns out to be a significant improvement in comparison with octogen and a very promising candidate for the role of the new "best explosive in the world."

Explosive substances have long been a part of human life. About what they are, where they are used and what are the rules for their storage, this article will tell.

A bit of history

From time immemorial, man has tried to create substances that, with a certain impact from the outside, caused an explosion. Naturally, this was not done for peaceful purposes. And one of the first widely known explosive substances was the legendary Greek fire, the recipe of which is still not exactly known. This was followed by the creation of gunpowder in China around the 7th century, which, on the contrary, was first used for entertainment purposes in pyrotechnics, and only then adapted for military needs.

For several centuries, the opinion was established that gunpowder is the only explosive known to man. Only at the end of the XVIII century was discovered silver fulminate, which is not unknown under the unusual name "explosive silver". Well, after this discovery, picric acid, "explosive mercury", pyroxylin, nitroglycerin, TNT, hexogen, and so on appeared.

Concept and classification

Speaking plain language, explosive substances are special substances or their mixtures, which, under certain conditions, can explode. These conditions can be a rise in temperature or pressure, a shock, a blow, sounds of specific frequencies, as well as intense lighting or even a light touch.

For example, one of the most famous and widespread explosive substances is acetylene. It is a colorless gas, which is also odorless in its pure form and is lighter than air. The acetylene used in production has a pungent smell, which is given to it by impurities. It has gained wide distribution in gas welding and cutting of metals. Acetylene can explode at 500 degrees Celsius or on prolonged contact with copper, as well as silver on impact.

At the moment, a lot of explosive substances are known. They are classified according to many criteria: composition, physical condition, explosive properties, directions of application, degree of danger.

According to the direction of application, explosives can be:

• industrial (used in many industries: from mining to material processing);
• experimental-experimental;
• the military;
• special purpose;
• anti-social use (often this includes homemade mixtures and substances that are used for terrorist and hooligan purposes).

Degree of danger

Also, as an example, explosive substances can be considered according to their degree of danger. In the first place are gases based on hydrocarbons. These substances are prone to random detonation. These include chlorine, ammonia, freons and so on. According to statistics, almost a third of the incidents in which explosives are the main actors involve hydrocarbon-based gases.

This is followed by hydrogen, which under certain conditions (for example, a combination with air in a ratio of 2:5) becomes the most explosive. Well, they close this top three in terms of the degree of danger of a pair of liquids that are prone to ignition. First of all, these are vapors of fuel oil, diesel fuel and gasoline.

Explosives in the military

Explosives find use in military affairs everywhere. There are two types of explosion: combustion and detonation. Due to the fact that gunpowder burns, when it explodes in a confined space, it is not the destruction of the cartridge case that occurs, but the formation of gases and the departure of a bullet or projectile from the barrel. TNT, RDX or ammonal just detonate and create an explosive wave, the pressure rises sharply. But in order for the detonation process to occur, an external impact is necessary, which can be:

• mechanical (impact or friction);
• thermal (flame);
• chemical (the reaction of an explosive with some other substance);
• detonation (there is an explosion of one explosive next to another).

Based on the last point, it becomes clear that two large classes of explosives can be distinguished: composite and individual. The former mainly consist of two or more substances that are not chemically related. It happens that individually such components are not capable of detonation and can only exhibit this property when in contact with each other.

Also, in addition to the main components, various impurities may be present in the composition of the composite explosive. Their purpose is also very wide: regulation of sensitivity or explosiveness, weakening of explosive characteristics or their strengthening. Since in recent times world terrorism is spreading more and more through impurities, it has become possible to find out where the explosive was made and to find it with the help of sniffer dogs.

Everything is clear with individual ones: sometimes they do not even need oxygen for a positive thermal output.

Brisance and explosiveness

Usually, in order to understand the power and strength of an explosive, it is necessary to have an understanding of such characteristics as brisance and explosiveness. The first means the ability to destroy surrounding objects. The higher the brisance (which, by the way, is measured in millimeters), the better the substance is suitable as a filling for an aerial bomb or projectile. Explosives with high brisance will create a strong shock wave and give high speed to flying fragments.

Explosiveness, on the other hand, means the ability to throw out surrounding materials. It is measured in cubic centimeters. Explosives with high explosiveness are often used when working with soil.

Safety precautions when working with explosive substances

The list of injuries that a person can receive due to accidents associated with explosives is very, very extensive: thermal and chemical burns, contusion, nervous shock from a blow, injuries from fragments of glass or metal utensils in which explosive substances were located, damage eardrum. Therefore, safety precautions when working with explosive substances have their own characteristics. For example, when working with them, it is necessary to have a safety screen made of thick organic glass or other durable material. Also, those who directly work with explosive substances must wear a protective mask or even a helmet, gloves and an apron made of durable material.

Storage of explosive substances also has its own characteristics. For example, their illegal storage has consequences in the form of liability, according to the Criminal Code of the Russian Federation. Dust contamination of stored explosives must be prevented. Containers with them must be tightly closed so that vapors do not enter the environment. An example would be toxic explosives whose vapors can cause both headache and dizziness and paralysis. Combustible explosives are stored in isolated warehouses that have fireproof walls. Places where explosive chemicals are located must be equipped with fire fighting equipment.

Epilogue

So, explosives can be both a faithful helper to a person, and an enemy if handled and stored improperly. Therefore, it is necessary to follow the safety rules as accurately as possible, and also not to try to pretend to be a young pyrotechnician and make any handicraft explosives.

EXPLOSIVES (a. explosives, blasting agents; n. Sprengstoffe; f. explosifs; and. explosivos) are chemical compounds or mixtures of substances capable, under certain conditions, of an extremely fast (explosive) self-propagating chemical transformation with the release of heat and the formation of gaseous products.

Explosives can be substances or mixtures of any state of aggregation. Widespread use in the so-called condensed explosives, which are characterized by a high volumetric concentration of thermal energy. Unlike conventional fuels, which require gaseous input for their combustion, such explosives release heat as a result of intramolecular decomposition processes or interaction reactions between the constituent parts of the mixture, their decomposition products or gasification. The specific nature of the release of thermal energy and its conversion into the kinetic energy of the explosion products and the energy of the shock wave determines the main field of application of explosives as a means of crushing and destroying solid media (mainly) and structures and moving the crushed mass (see).

Depending on the nature of the external influence, chemical transformations of explosives occur: when heated below the temperature of self-ignition (flash) - a relatively slow thermal decomposition; during ignition - combustion with the movement of the reaction zone (flame) through the substance at a constant speed of the order of 0.1-10 cm / s; with shock-wave action - detonation of explosives.

Classification of explosives. There are several signs of the classification of explosives: according to the main forms of transformation, purpose and chemical composition. Depending on the nature of the transformation under operating conditions, explosives are divided into propellant (or) and. The former are used in the combustion mode, for example, in firearms and rocket engines, the latter in the mode, for example, in ammunition and on. High explosives used in industry are called. Usually, only high explosives are classified as proper explosives. In chemical terms, the listed classes can be completed with the same compounds and substances, but processed differently or taken when mixed in different proportions.

By susceptibility to external influences, high explosives are divided into primary and secondary. Primary explosives include explosives that can explode in a small mass when ignited (rapid transition from combustion to detonation). They are also much more sensitive to mechanical stress than secondary ones. The detonation of secondary explosives is easiest to cause (initiate) by shock-wave action, and the pressure in the initiating shock wave should be of the order of several thousand or tens of thousands of MPa. In practice, this is carried out with the help of small masses of primary explosives placed in, the detonation in which is excited by a beam of fire and is transmitted by contact to a secondary explosive. Therefore, primary explosives are also called. Other types of external action (ignition, spark, impact, friction) lead to the detonation of secondary explosives only under special and difficult-to-regulate conditions. For this reason, the widespread and purposeful use of high explosives in the detonation mode in civil and military explosive technology began only after the invention of the blasting cap as a means of initiating detonation in secondary explosives.

According to the chemical composition, explosives are divided into individual compounds and explosive mixtures. In the first, chemical transformations during an explosion occur in the form of a monomolecular decomposition reaction. The end products are stable gaseous compounds, such as oxide and dioxide, water vapor.

In explosive mixtures, the transformation process consists of two stages: the decomposition or gasification of the components of the mixture and the interaction of the decomposition products (gasification) with each other or with particles of non-decomposing substances (for example, metals). The most common secondary individual explosives are nitrogen-containing aromatic, aliphatic heterocyclic organic compounds, including nitro compounds ( , ), nitroamines ( , ), nitroesters ( , ). Of the inorganic compounds, for example, ammonium nitrate has weak explosive properties.

The variety of explosive mixtures can be reduced to two main types: those consisting of oxidizers and combustibles, and mixtures in which the combination of components determines the operational or technological qualities of the mixture. Oxidizer-fuel mixtures are designed for the fact that a significant part of the thermal energy is released during the explosion as a result of secondary oxidation reactions. The components of these mixtures can be both explosive and non-explosive compounds. Oxidizing agents, as a rule, release free oxygen during decomposition, which is necessary for the oxidation (with heat release) of combustible substances or their decomposition products (gasification). In some mixtures (for example, metal powders contained as fuel), substances that emit not oxygen, but oxygen-containing compounds (water vapor, carbon dioxide) can also be used as oxidizing agents. These gases react with metals to release heat. An example of such a mixture is .

As combustibles, various kinds of natural and synthetic organic substances are used, which, during an explosion, emit products of incomplete oxidation (carbon monoxide) or combustible gases (, ) and solid substances (soot). The most common type of blasting explosive mixtures of the first type are explosives containing ammonium nitrate as an oxidizing agent. Depending on the type of fuel, they, in turn, are divided into, ammotols and ammonals. Less common are chlorate and perchlorate explosives, which include potassium chlorate and ammonium perchlorate as oxidizers, oxyliquites - mixtures of liquid oxygen with a porous organic absorber, mixtures based on other liquid oxidizers. Explosive mixtures of the second type include mixtures of individual explosives, such as dynamites; mixtures of TNT with RDX or PETN (pentolite), most suitable for manufacturing.

In mixtures of both types, in addition to the indicated components, depending on the purpose of the explosives, other substances can also be introduced to give the explosive some operational properties, for example, increasing the susceptibility to the means of initiation, or, conversely, reducing the sensitivity to external influences; hydrophobic additives - to make the explosive water resistant; plasticizers, flame retardant salts - to impart safety properties (see Safety explosives). The main operational characteristics of explosives (detonation and energy characteristics and physical and chemical properties of explosives) depend on the recipe composition of explosives and manufacturing technology.

The detonation characteristic of explosives includes detonation capability and susceptibility to detonation impulse. Reliability and reliability of blasting depend on them. For each explosive at a given density, there is a critical charge diameter at which the detonation propagates steadily along the entire length of the charge. A measure of the susceptibility of explosives to a detonation pulse is the critical pressure of the initiating wave and its duration, i.e. the value of the minimum initiating impulse. It is often expressed in terms of the mass of some primary explosive or secondary explosive with known detonation parameters. Detonation is excited not only by contact detonation of the initiating charge. It can also be transmitted through inert media. This is of great importance for, consisting of several cartridges, between which there are jumpers made of inert materials. Therefore, for cartridge explosives, the rate of detonation transmission over a distance through various media (usually through air) is checked.

Energy characteristics of explosives. The ability of explosives to perform mechanical work during an explosion is determined by the amount of energy released in the form of heat during explosive transformation. Numerically, this value is equal to the difference between the heat of formation of the explosion products and the heat of formation (enthalpy) of the explosive itself. Therefore, the coefficient of conversion of thermal energy into work for metal-containing and safety explosives that form solid products (metal oxides, flame retardant salts) with high heat capacity during an explosion is lower than for explosives that form only gaseous products. On the ability of explosives to local crushing or blasting action of the explosion, see Art. .

Changes in the properties of explosives can occur as a result of physical and chemical processes, the influence of temperature, humidity, under the influence of unstable impurities in the composition of explosives, etc. Depending on the type of closure, a guaranteed period of storage or use of explosives is established, during which the normalized indicators either should not change, or their change occurs within the established tolerance.

The main indicator of safety in the handling of explosives is their sensitivity to mechanical and thermal influences. It is usually estimated experimentally in the laboratory using special methods. In connection with the massive introduction of mechanized methods of moving large masses of loose explosives, they are subject to the requirements of minimal electrification and low sensitivity to the discharge of static electricity.

History reference. Black (smoky) gunpowder, invented in China (seventh century), was the first of the explosives. It has been known in Europe since the 13th century. From the 14th century gunpowder was used as a propellant in firearms. In the 17th century (for the first time in one of the mines in Slovakia) gunpowder was used in blasting in mining, as well as for equipping artillery grenades (explosive cores). The explosive transformation of black powder was excited by ignition in the explosive combustion mode. In 1884, French engineer P. Viel proposed smokeless powder. In the 18-19 centuries. a number of chemical compounds with explosive properties were synthesized, including picric acid, pyroxylin, nitroglycerin, TNT, etc., however, their use as blasting detonating explosives became possible only after the discovery by the Russian engineer D. I. Andrievsky (1865) and Swedish inventor A. Nobel (1867) explosive fuse (detonator cap). Prior to this, in Russia, at the suggestion of N. N. Zinin and V. F. Petrushevsky (1854), nitroglycerin was used in explosions instead of black powder in the explosive combustion mode. The explosive mercury itself was obtained as early as the end of the 17th century. and again by the English chemist E. Howard in 1799, but its ability to detonate was not known at that time. After the discovery of the phenomenon of detonation, high explosives were widely used in mining and military affairs. Among industrial explosives, initially according to the patents of A. Nobel, gurdynamites were most widely used, then plastic dynamites, powdered nitroglycerin mixed explosives. Ammonium nitrate explosives were patented as early as 1867 by I. Norbin and I. Olsen (Sweden), but their practical use as industrial explosives and for filling ammunition did not begin until World War I (1914–18). Safer and more economical than dynamites, they began to be used on an increasing scale in industry in the 30s of the 20th century.

After the Great Patriotic War 1941-45 ammonium nitrate explosives, initially predominantly in the form of finely dispersed ammonites, became the dominant type of commercial explosives in the CCCP. In other countries, the process of mass replacement of dynamites with ammonium nitrate explosives began somewhat later, approximately from the mid-1950s. From the 70s. the main types of industrial explosives are granular and water-containing ammonium nitrate explosives of the simplest composition, not containing nitro compounds or other individual explosives, as well as mixtures containing nitro compounds. Finely dispersed ammonium nitrate explosives have retained their importance mainly for the manufacture of militant cartridges, as well as for some special types of blasting. Individual explosives, especially TNT, are widely used for the manufacture of detonators, as well as for long-term loading of flooded wells, in pure form () and in highly water-resistant explosive mixtures, granular and suspension (water-containing). For deep apply and.