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Pyrophoric flares may have reduced effectiveness at high altitudes, due to lower air temperature and lower availability of oxygen; however oxygen can be co-ejected with the pyrophoric fuel. [ 13 ] The advantage of alkyl aluminium and similar compounds is the high content of carbon and hydrogen, resulting in bright emission lines similar to ...
The creation of sparks from metals is based on the pyrophoricity of small metal particles, and pyrophoric alloys are made for this purpose. [2] Practical applications include the sparking mechanisms in lighters and various toys, using ferrocerium; starting fires without matches, using a firesteel; the flintlock mechanism in firearms; and spark testing ferrous metals.
Other similar intermetallic compositions used in pyrotechnics are titanium-boron and aluminium-palladium ("Pyrofuze"). These foils are made in a range of thicknesses, e.g. 60, 80, 100, and 150 micrometers. The flame front propagation rate ranges generally between 7.5–9 m/s. The reaction temperature can reach up to 1500 °C for a millisecond.
Pyrotechnic initiators are often controlled electrically (called electro-pyrotechnic initiators), e.g. using a heated bridgewire or a bridge resistor. They are somewhat similar to blasting caps or other detonators, but they differ in that there is no intention to produce a shock wave. An example of such pyrotechnic initiator is an electric match.
A pyrotechnic composition is a substance or mixture of substances designed to produce an effect by heat, light, sound, gas/smoke or a combination of these, as a result of non-detonative self-sustaining exothermic chemical reactions. Pyrotechnic substances do not rely on oxygen from external sources to sustain the reaction.
Pyrotechnic compositions based on magnesium/polytetrafluoroethylene with stoichiometries from 25 wt% to 90 wt% magnesium are, according to German explosive legislation, the Koenen test (steel sleeve test), and BAM impact test, explosive substances.
Pyrotechnic valves have an extremely fast response time (time from the actuation signal reaching the device til the valve has closed/opened), often in the order of a few milliseconds. [ 1 ] Normally-closed pyro valves have a far lower leak rate than other valves, allowing them to hermetically seal propellant inside a tank to keep it from ...
Series 5 tests are used to determine if an article can be assigned to HD1.5 'Very Insensitive Explosive'; series 6 tests are used to determine the classification of an article within Hazard Divisions 1.1, 1.2, 1.3, or 1.4; and series 7 tests are used to determine if an article can be assigned to HD 1.6 as an article containing predominantly ...