Electric match

An electric match is a device that uses an externally applied electric current to ignite a combustible compound.

Use

Electric matches can be used in any application where source of heat is needed at a precisely controlled point in time, typically to ignite a propellant or explosive. A partial list of applications is: [cite web |url=http://www.electricmatch.com/disclm.html |title=MJG TECHNOLOGIES INC., DISCLAIMER AND TERMS OF SALE]
*Airbag deployment
*Pyrotechnics
*Military or commercial explosives
*Model rocketry

Construction and operation

Electric matches consist of two parts, a bridge wire and a pyrogen. The bridge wire is a heating element, typically in the form of a loop or coil of thin wire, which is encased in the pyrogen, which is a quantity of readily ignited combustible material. If the pyrogen is sufficiently conductive, it can act as the bridge wire as well. Electric matches also come with provisions for attaching an electrical current source, and they may be provided with a protective cover and/or a means to attach them to the device to be ignited.cite web |url=http://www.craftershome.net/FireStar/about.html |title=FIRESTAR ELECTRIC MATCH] [cite web |url=http://www.esteseducator.com/Pdf_files/Igniters.pdf |title=Intiters and Their Use |author=By Bob Cannon,Mary Roberts, Ann Grimm and Kathleen Greer |publisher=Estes] cite web |url=http://www.vk2zay.net/article.php/14 |title=Electrical Ingition]

To operate an electric match, a source of electricity of appropriate voltage and amperage is needed to provide current to the match. When sufficient electric current is passed through the bridge wire, the resistive heating causes the element to rise above the ignition temperature of the pyrogen, and the pyrogen begins to burn.

Electric matches may be regulated, as they can be used to ignite explosives; for amateur pyrotechnics use electric matches can be built from scratch or from kit form. Kits include the thin wire needed for the bridge wire, such as nichrome wire, along with components for mixing the pyrogen. Scratch built matches use thin wire which may be purchased or salvaged from sources such as light bulb filaments, and copper wiring.cite web |url=http://www.wichitabuggywhip.com/fireworks/ematch.html |title=Electric Matches]

In addition to the readily ignitable component of the electric match pyrogen, some matches may also add additional components to provide a hotter, longer lasting flame, for igniting items that are difficult to ignite. For example, igniters for solid fuel model rocket motors often include powdered metals, which provide a more heat and duration to the match flame, and a more reliable ignition of the motor.

ee also

*Tubes and primers for ammunition
* primers
*Blasting cap
*Pyrotechnic fastener
*Exploding-bridgewire detonator

References