【 Weak current College 】 explosive detonation and sensitivity---Power By 【 China power house network 】

First, the explosive detonation
　　
Each explosives have relative stability, to make it an explosion, you must provide certain external role supply enough energy to activate part of explosives. Fired explosive initiation of procedure is called. The explosive reaction explosion activation
　　
Need of activation energy known as initiation.
　　
Initiation to mainly in thermal, mechanical and explosive energy.
　　
Detonating explosives can ability to play, not only with the initiation of size, but also depends on the concentration of energy. According to the activation energy theory, reaction just have activation energy of activation molecules mutual contacts and collision to occur. Therefore, in order to make explosives, must have sufficient external energy make explosive elements becomes activated. The number of activation molecules, the more explosive reaction speed is higher. Initiation, external energy into explosives activation energy, resulting in a sufficient number of activation molecules and their mutual contact, collision and explosion effects.
　　
Second, the explosive sensitivity
　　
Explosive energy outside of initiating the degree of difficulty is called explosive sensitivity (or sensitivity). Explosive sensitivity level used to excite the explosive reaction required minimum ignition energy of what to measure. The required minimum ignition energy, said the explosives sensitivity is higher, on the contrary that the low sensitivity of explosives.
　　
Explosive on different forms of initiation can have different sensitivity. E.g. of TNT explosives on the mechanical action of sensitivity is low, but on EDM's sensitivity is higher. To study the different forms of initiation will ease of explosives, explosive sensitivity include: thermal, flame sensitivity, EDM sensitivity, shock sensitivity, friction sensitivity, shooting sensitivity, shock sensitivity and detonation sensitivity, etc. These sensitivity determination can be carried out through testing. If you spend a certain sense of explosives, for the production, storage, transport and use of risk. Therefore, in the explosive production process to try to change some sensitivity of explosives. Impact of the main factors of explosive sensitivity is as follows:
　　
(A) the chemical structure of explosives
　　
Explosive combination of molecular structure, the more vulnerable, their sensitivity is higher, on the contrary, the more low. Mixed-explosive sensitivity depends on the explosive structure most vulnerable components of sensitivity.
　　
(Ii) physical properties of explosives
　　
(1) the phase of explosives. Molten state of explosive than similar explosive solid state of sensitivity high, this is due to the explosive liquid from the solid phase shift to absorb the latent heat of melting, higher internal energy. In addition, when the liquid has a high vapor pressure, so very small things can be fired explosive.
　　
(2) explosive particle size. Explosives for violent explosive, smaller particles, the higher the sensitivity, this is because the larger the explosive particle surface area to receive the shock wave energy, the more easy for produces more hotspots and ease of ignition. However for explosive, the grain, the higher the sensitivity, on the contrary, because a larger gap between the grains are also more conducive to the formation of the HotSpot.
　　
(3) the charge density. Powder explosive charge density exceeds a certain value, as the density increases, the sensitivity drops of explosives. As the density increases, the porosity is reduced, is not conducive to absorb heat.
　　
(4) of tiny bubbles. Explosive containing tiny air bubbles in the explosion can occur under adiabatic compression, is a major cause of the HotSpot. The presence of micro-bubbles can improve the sensitivity of explosives.
　　
(5) admixtures. Explosives in person a certain amount of admixtures to make explosives sensitivity change significantly. High melting point and high hardness, thermal conductivity of admixtures such as quartz sand, glass fragments, etc., can cause explosive impact, friction sensitivity. And paraffin, graphite and other soft admixtures, cannot constitute the explosive particle surface coated with a thin layer, which weakened the medicine or particles friction puckering explosives sensitivity reduction.
　　
Third, anti-explosive
　　
A charge (volume) after the explosion, and it is not in contact with neighboring charge (volume) explosion phenomenon, known as anti-explosive. Anti-explosive in part reflects the explosive on detonation of sensitivity. The first explosion of a certain amount of explosives is called active charge, was induced by a certain amount of dynamite explosion known as passive charge. Active charge can induce passive charge distance called anti-explosive distance. Anti-explosive distance decided to take the initiative of the explosive nature of the charge and the charge, passive charge to Shockwave's sensitivity, as well as the charge the nature of the media.
　　
Diameter between anti-explosive distance can usually be determined by testing. Test, the same kind of explosive two cartridge along the axis at a certain distance from the flat on the solid foundation of sand soil, one cartridge capped as active charge, another cartridge as passive charge, then detonated. According to the formation of fried hang and no residue of explosives and to judge the power shell, anti-explosive through a series of tests to identify phase Pro diameter to anti-explosive maximum distance.