# Reactive material > Mediated Wiki article. Canonical URL: https://mediated.wiki/source/Reactive_material > Markdown URL: https://mediated.wiki/source/Reactive_material.md > Source: https://en.wikipedia.org/wiki/Reactive_material > Source revision: 1049050698 > License: Creative Commons Attribution-ShareAlike 4.0 International (https://creativecommons.org/licenses/by-sa/4.0/) In the [U.S. military](/source/United_States_Department_of_Defense), **reactive materials** (**RM**) are a new class of materials currently being investigated by the [Office of Naval Research](/source/Office_of_Naval_Research) and others as a means to increase the [lethality](/source/Lethality) of direct-hit or fragmentation [warheads](/source/Warhead). Reactive materials are similar to [insensitive high explosives](/source/Insensitive_munitions#Insensitive_high_explosives), but are usually [thermite](/source/Thermite)-like [pyrotechnic compositions](/source/Pyrotechnic_composition) of two or more nonexplosive solid materials, which stay inert and do not react with each other until subjected to a sufficiently strong mechanical, electrical or laser stimulus, after which they undergo fast burning or [explosion](/source/Explosion) with release of high amount of [chemical energy](/source/Chemical_energy) in addition to their [kinetic energy](/source/Kinetic_energy). Fragments or projectiles made of such materials have therefore greater damaging effect than inert ones, with expected lethality increase up to 500%. The material classes under investigation are [thermites](/source/Thermite), [intermetallic](/source/Intermetallic) compounds, metal-polymer mixtures (e.g., [magnesium/teflon/viton](/source/Magnesium%2Fteflon%2Fviton)-like), [metastable intermolecular composites](/source/Metastable_intermolecular_composite) (MIC), matrix materials, and [hydrides](/source/Hydride).[1] These materials must be strong enough to act as structural components, be sufficiently stable to survive handling and launch, to penetrate a target, and sufficiently unstable to reliably ignite on impact. The mixtures under investigation include one or more finely powdered (down to [nanoparticle](/source/Nanoparticle) size) [metalloids](/source/Metalloid) or metals like [aluminium](/source/Aluminium), [magnesium](/source/Magnesium), [zirconium](/source/Zirconium), [titanium](/source/Titanium), [tungsten](/source/Tungsten), [tantalum](/source/Tantalum), [uranium](/source/Uranium)[2] or [hafnium](/source/Hafnium), with one or more oxidizers like [teflon](/source/Teflon) or other [fluoropolymer](/source/Fluoropolymer), pressed or [sintered](/source/Sintering) or bonded by other method to a compact, high-density mass. To achieve a suitable [reaction rate](/source/Reaction_rate) and insensitivity to impact, friction, and [electrostatic discharge](/source/Electrostatic_discharge), fuel particles have sizes usually between 1-250 μm.[3][4] A standard composition is aluminium-teflon (Al-PTFE). Metals which can form [intermetallic](/source/Intermetallic) compounds by an [exothermic](/source/Exothermic) reaction are another class of candidate materials. An example is a [laminate](/source/Laminate) of thin alternating layers of [aluminum](/source/Aluminum) and [nickel](/source/Nickel), commercially available as [NanoFoil](/source/NanoFoil). The RM weapons under development include an [active protection system](/source/Active_protection_system) defensive grenade for intercepting incoming missiles or grenades and detonating them at a safe distance, and the [BattleAxe](https://en.wikipedia.org/w/index.php?title=BattleAxe_(warhead)&action=edit&redlink=1) warhead that covers a wide area with RM fragments with devastating results to [soft targets](/source/Soft_target), while the unexploded fragments left behind have very low lethality versus conventional [cluster bomb](/source/Cluster_bomb) remains. Under research are materials with high [mechanical strength](/source/Mechanical_strength), high density, high [energy density](/source/Energy_density), and which can rapidly convert from a consolidated structural material to fine powder with large surface area, be dispersed and then ignited to produce a large [thermobaric](/source/Thermobaric_weapon) blast.[5] A [palladium](/source/Palladium)-clad [aluminum](/source/Aluminum) wire, known under trademark *Pyrofuze*, is used as a [pyrotechnic initiator](/source/Pyrotechnic_initiator). Reactive materials also have non-weapon uses. Thin layers of reactive materials, clad with a [solder](/source/Solder), are used for [reactive bonding](/source/Reactive_bonding), e.g., in electronics, or for [brazing](/source/Brazing), such as in [composite armor](/source/Composite_armor) plates. ## References 1. **[^](#cite_ref-1)** Committee on Advanced Energetic Materials and Manufacturing Technologies, National Research Council (2004). [*Advanced Energetic Materials*](http://books.nap.edu/openbook.php?record_id=10918&page=20). Washington D.C., USA: National Academies Press. pp. 20–23. [ISBN](/source/ISBN_(identifier)) [978-0-309-09160-2](https://en.wikipedia.org/wiki/Special:BookSources/978-0-309-09160-2). Retrieved 16 August 2011. 1. **[^](#cite_ref-2)** Patents [https://www.google.fr/patents/US7191709](https://www.google.fr/patents/US7191709) and [https://www.google.fr/patents/US7194961](https://www.google.fr/patents/US7194961) make explicit reference to the use of uranium 1. **[^](#cite_ref-3)** [US patent 6593410](https://worldwide.espacenet.com/textdoc?DB=EPODOC&IDX=US6593410), Nielson, Daniel B.; Tanner, Richard L. & Lund, Gary K., "High Strength Reactive Materials", published 2003-05-22, issued 2003-07-15, assigned to Alliant Techsystems Inc. 1. **[^](#cite_ref-4)** [US patent 6962634](https://worldwide.espacenet.com/textdoc?DB=EPODOC&IDX=US6962634), Nielson, Daniel B.; Truitt, Richard M. & Rasmussen, Nikki, "Low temperature, extrudable, high density reactive materials", published 2004-02-05, issued 2005-11-08, assigned to Alliant Techsystems Inc. 1. **[^](#cite_ref-5)** ["Reactive Material Structures (RMS)"](http://www.darpa.mil/Our_Work/DSO/Programs/Reactive_Material_Structures_%28RMS%29.aspx). *Defense Advanced Research Projects Agency*. Retrieved 16 August 2011. ## External links - [Popular Mechanics: Better Bombs: Scientists develop metal that explodes on impact](http://www.popularmechanics.com/technology/military_law/4219350.html) - [SpaceRef: Better warheads through plastic](http://www.spaceref.com/news/viewpr.html?pid=9956) - [Wired: In Next-Gen Bullets and Bombs, Even the Casing Explodes](https://www.wired.com/politics/security/news/2008/05/reactive_revolutions) --- Adapted from the Wikipedia article [Reactive material](https://en.wikipedia.org/wiki/Reactive_material) by Wikipedia contributors ([contributor history](https://en.wikipedia.org/wiki/Reactive_material?action=history)). Available under [Creative Commons Attribution-ShareAlike 4.0 International](https://creativecommons.org/licenses/by-sa/4.0/). Changes may have been made.