types of explosive materials

Classification of explosive materials[edit]

By sensitivity[edit]

Primary explosive[edit]

A primary explosive is an explosive that is extremely sensitive to stimuli such as impact, friction, heat, static electricity, or electromagnetic radiation. Some primary explosives are also known as contact explosives. A relatively small amount of energy is required for initiation. As a very general rule, primary explosives are considered to be those compounds that are more sensitive than PETN. As a practical measure, primary explosives are sufficiently sensitive that they can be reliably initiated with a blow from a hammer; however, PETN can also usually be initiated in this manner, so this is only a very broad guideline. Additionally, several compounds, such as nitrogen triiodide, are so sensitive that they cannot even be handled without detonating. Nitrogen triiodide is so sensitive that it can be reliably detonated by exposure to alpha radiation; it is the only explosive for which this is true.

Primary explosives are often used in detonators or to trigger larger charges of less sensitive secondary explosives. Primary explosives are commonly used in blasting caps and percussion caps to translate a physical shock signal. In other situations, different signals such as electrical/physical shock, or, in the case of laser detonation systems, light, are used to initiate an action, i.e., an explosion. A small quantity, usually milligrams, is sufficient to initiate a larger charge of explosive that is usually safer to handle.

Examples of primary high explosives are:

• Acetone peroxide
• Alkali metal ozonides
• Ammonium permanganate
• Ammonium chlorate
• Azidotetrazolates
• Azo-clathrates
• Benzoyl peroxide
• Benzvalene
• Chlorine oxides
• Copper(I) acetylide
• Copper(II) azide
• Cumene hydroperoxide
• Cyanogen azide
• Cyanuric triazide
• Diacetyl peroxide
• 1-Diazidocarbamoyl-5-azidotetrazole
• Diazodinitrophenol
• Diazomethane
• Diethyl ether peroxide
• 4-Dimethylaminophenylpentazole
• Disulfur dinitride
• Ethyl azide
• Explosive antimony
• Fluorine perchlorate
• Fulminic acid
• Halogen azides:
  • Fluorine azide
  • Chlorine azide
  • Bromine azide
• Hexamethylene triperoxide diamine
• Hydrazoic acid
• Hypofluorous acid
• Lead azide
• Lead styphnate
• Lead picrate^[13]
• Manganese heptoxide
• Mercury(II) fulminate
• Mercury nitride
• Methyl ethyl ketone peroxide
• Nickel hydrazine nitrate^[14]
• Nickel hydrazine perchlorate
• Nitrogen trihalides:
  • Nitrogen trichloride
  • Nitrogen tribromide
  • Nitrogen triiodide
• Nitroglycerin
• Nitronium perchlorate
• Nitrotetrazolate-N-oxides
• Octaazacubane
• Pentazenium hexafluoroarsenate
• Peroxy acids
• Peroxymonosulfuric acid
• Selenium tetraazide
• Silicon tetraazide
• Silver azide
• Silver acetylide
• Silver fulminate
• Silver nitride
• Sodium azide
• Tellurium tetraazide
• tert-Butyl hydroperoxide
• Tetraamine copper complexes
• Tetraazidomethane
• Tetrazene explosive
• Tetranitratoxycarbon
• Tetrazoles
• Titanium tetraazide
• Triazidomethane
• Xenon dioxide
• Xenon oxytetrafluoride
• Xenon tetroxide
• Xenon trioxide

Secondary explosive[edit]

A secondary explosive is less sensitive than a primary explosive and requires substantially more energy to be initiated. Because they are less sensitive, they are usable in a wider variety of applications and are safer to handle and store. Secondary explosives are used in larger quantities in an explosive train and are usually initiated by a smaller quantity of a primary explosive.

Examples of secondary explosives include TNT and RDX.

Tertiary explosive[edit]

Tertiary explosives, also called blasting agents, are so insensitive to shock that they cannot be reliably detonated by practical quantities of primary explosive, and instead require an intermediate explosive booster of secondary explosive. These are often used for safety and the typically lower costs of material and handling. The largest consumers are large-scale mining and construction operations.

ANFO is an example of a tertiary explosive.