Editing Composite material (section)

===Composite materials===

[[File:Concrete aggregate grinding.JPG|thumb|Concrete is a mixture of adhesive and aggregate, giving a robust, strong material that is very widely used.]]
[[Concrete]] is the most common artificial composite material of all. {{as of|2009}}, about 7.5 billion cubic metres of concrete are made each year.<ref>{{cite web |title=Minerals commodity summary – cement – 2009
 |publisher=US [[United States Geological Survey]] |date=1 June 2007 |url=http://minerals.usgs.gov/minerals/pubs/commodity/cement/index.html |access-date=16 January 2008 |url-status=live |archive-url=https://web.archive.org/web/20071213052530/http://minerals.usgs.gov/minerals/pubs/commodity/cement/index.html |archive-date=13 December 2007}}<!--Computed by taking 2007 figure for world concrete production and the mix at http://en.wikipedia.org/wiki/Concrete#Regular_concrete and computing the volume--></ref>
Concrete typically consists of loose stones ([[construction aggregate]]) held with a matrix of [[cement]]. Concrete is an inexpensive material resisting large compressive forces,<ref>{{cite web |url=http://www.constructionknowledge.net/concrete/concrete_basics.php |title=Slabs On Grade |publisher=Construction Knowldegs.net |access-date=January 3, 2018 |url-status=live |archive-url=https://web.archive.org/web/20171002174044/http://www.constructionknowledge.net/concrete/concrete_basics.php |archive-date=October 2, 2017}}</ref> however, susceptible to [[tensile load]]ing.<ref>{{cite web |url=https://theconstructor.org/practical-guide/concrete-under-tension/6805/ |title=Behaviour of Concrete Under Tension |publisher=The Constructor |access-date=January 3, 2018 |url-status=live |archive-url=https://web.archive.org/web/20180104192350/https://theconstructor.org/practical-guide/concrete-under-tension/6805/ |archive-date=January 4, 2018 |date=2012-12-06}}</ref> To give concrete the ability to resist being stretched, steel bars, which can resist high stretching (tensile) forces, are often added to concrete to form [[reinforced concrete]].<ref>{{cite web |title=Reinforced concrete |url=https://www.designingbuildings.co.uk/wiki/Reinforced_concrete |access-date=2020-12-17 |website=www.designingbuildings.co.uk |language=en-gb |archive-date=2016-07-11 |archive-url=https://web.archive.org/web/20160711094546/https://www.designingbuildings.co.uk/wiki/Reinforced_concrete |url-status=live}}</ref>

[[File:Cfaser_haarrp.jpg|thumb|A black [[carbon fibre]] (used as a reinforcement component) compared to a [[human hair]]]]
[[Fibre-reinforced plastic|Fibre-reinforced polymers]] include [[carbon-fiber-reinforced polymers]] and [[glass-reinforced plastic]]. If classified by matrix then there are [[thermoplastic composites]], [[short fiber thermoplastics|short fibre thermoplastics]], [[long fibre thermoplastic]]s or [[long-fiber-reinforced thermoplastic]]s. There are numerous [[thermoset]] composites, including [[paper composite panels]]. Many advanced [[thermoset polymer matrix]] systems usually incorporate [[aramid]] [[fibre]] and [[carbon fibre]] in an [[epoxy resin]] matrix.<ref>{{cite web |last=Reeve |first=Scott |title=3 Reasons to use Fiber-Reinforced Polymer (FRP) |url=https://www.compositeadvantage.com/blog/3-reasons-use-fiber-reinforced-polymer-frp |access-date=2020-12-17 |website=www.compositeadvantage.com |language=en-us |archive-date=2020-10-24 |archive-url=https://web.archive.org/web/20201024143918/https://www.compositeadvantage.com/blog/3-reasons-use-fiber-reinforced-polymer-frp |url-status=live}}</ref><ref>{{cite web |date=2014-08-05 |title=A Beginner's Guide to Fiber Reinforced Plastics (FRP's) - Craftech Industries - High-Performance Plastics - (518) 828-5001 |url=https://www.craftechind.com/beginners-guide-fiber-reinforced-plastics-frps/ |access-date=2020-12-17 |website=Craftech Industries |language=en-US |archive-date=2017-05-14 |archive-url=https://web.archive.org/web/20170514110108/https://www.craftechind.com/beginners-guide-fiber-reinforced-plastics-frps/ |url-status=dead}}</ref>

[[Shape-memory polymer]] composites are high-performance composites, formulated using fibre or fabric reinforcements and shape-memory polymer resin as the matrix. Since a shape-memory polymer resin is used as the matrix, these composites have the ability to be easily manipulated into various configurations when they are heated above their activation temperatures and will exhibit high strength and stiffness at lower temperatures. They can also be reheated and reshaped repeatedly without losing their material properties. These composites are ideal for applications such as lightweight, rigid, deployable structures; rapid manufacturing; and dynamic reinforcement.<ref>{{cite web |title=Shape Memory Polymers - A Complete Guide |url=https://www.bpf.co.uk/plastipedia/applications/shape-memory-polymer.aspx |access-date=2020-12-17 |website=www.bpf.co.uk |archive-date=2021-05-23 |archive-url=https://web.archive.org/web/20210523194900/https://www.bpf.co.uk/plastipedia/applications/shape-memory-polymer.aspx |url-status=live}}</ref><ref>{{cite web |title=Shape Memory Polymers {{!}} Sheffield Hallam University|url=https://www.shu.ac.uk/research/specialisms/materials-and-engineering-research-institute/what-we-do/expertise/shape-memory-polymers|access-date=2020-12-17|website=www.shu.ac.uk|archive-date=2021-05-23|archive-url=https://web.archive.org/web/20210523194851/https://www.shu.ac.uk/research/specialisms/materials-and-engineering-research-institute/what-we-do/expertise/shape-memory-polymers|url-status=live}}</ref>

[[High strain composite structure|High strain composites]] are another type of high-performance composites that are designed to perform in a high deformation setting and are often used in deployable systems where structural flexing is advantageous.{{citation needed|date =August 2017}} Although high strain composites exhibit many similarities to shape-memory polymers, their performance is generally dependent on the fibre layout as opposed to the resin content of the matrix.<ref>{{cite web |title=Tensile Fiber Failure on High Strain Composites |url=https://www.colorado.edu/faculty/lopezjimenez/sites/default/files/attached-files/tensile_fiber_failure_on_high_strain_composites.pdf |access-date=Dec 17, 2020 |website=University of Colorado, Boulder |archive-date=May 23, 2021 |archive-url=https://web.archive.org/web/20210523194900/https://www.colorado.edu/faculty/lopezjimenez/sites/default/files/attached-files/tensile_fiber_failure_on_high_strain_composites.pdf |url-status=live}}</ref>

Composites can also use metal fibres reinforcing other metals, as in [[metal matrix composite]]s (MMC)<ref>{{cite web |title=7: Metal Matrix Composites {{!}} School of Materials Science and Engineering|url=http://www.materials.unsw.edu.au/tutorials/online-tutorials/7-metal-matrix-composites|access-date=2020-12-17|website=www.materials.unsw.edu.au|archive-date=2021-01-25|archive-url=https://web.archive.org/web/20210125180839/http://www.materials.unsw.edu.au/tutorials/online-tutorials/7-metal-matrix-composites|url-status=live}}</ref> or [[ceramic matrix composite]]s (CMC),<ref>{{cite web |title=What are Ceramic Matrix Composites? |url=https://llfurnace.com/blog/what-are-ceramic-matrix-composites/ |work=L&L Special Furnace |date=30 August 2018 }}</ref> which includes [[bone mineral|bone]] ([[hydroxyapatite]] reinforced with [[collagen]] fibres), [[cermet]] (ceramic and metal), and [[concrete]]. Ceramic matrix composites are built primarily for [[fracture toughness]], not for strength. Another class of composite materials involve woven fabric composite consisting of longitudinal and transverse laced yarns. Woven fabric composites are flexible as they are in form of fabric.

Organic matrix/ceramic aggregate composites include [[asphalt concrete]], [[polymer concrete]], [[mastic asphalt]], mastic roller hybrid, [[dental composite]], [[syntactic foam]], and [[nacre|mother of pearl]].<ref>{{cite web |title=Composite Material |url=https://www.hi-techindia.in/composite-material |access-date=2020-12-21 |website=hi-techindia |language=en |archive-date=2021-03-03 |archive-url=https://web.archive.org/web/20210303031856/https://www.hi-techindia.in/composite-material |url-status=live}}</ref> [[Chobham armour]] is a special type of [[composite armour]] used in military applications.{{citation needed|date=October 2023}}

Additionally, [[thermoplastic]] composite materials can be formulated with specific metal powders resulting in materials with a density range from 2 g/cm<sup>3</sup> to 11 g/cm<sup>3</sup> (same density as lead). The most common name for this type of material is "high gravity compound" (HGC), although "lead replacement" is also used. These materials can be used in place of traditional materials such as aluminium, stainless steel, brass, bronze, copper, lead, and even tungsten in weighting, balancing (for example, modifying the centre of gravity of a tennis [[racquet]]), vibration damping, and radiation shielding applications. High density composites are an economically viable option when certain materials are deemed hazardous and are banned (such as lead) or when secondary operations costs (such as machining, finishing, or coating) are a factor.<ref>{{cite web |date=2001-02-15 |title=Thermoplastic Composites - An Introduction |url=https://www.azom.com/article.aspx?ArticleID=85 |access-date=2020-12-17 |website=AZoM.com |language=en |archive-date=2012-04-05 |archive-url=https://web.archive.org/web/20120405141717/https://www.azom.com/article.aspx?ArticleID=85 |url-status=live}}</ref>

There have been several studies indicating that interleaving stiff and brittle epoxy-based [[carbon-fiber-reinforced polymers|carbon-fiber-reinforced polymer]] laminates with flexible thermoplastic laminates can help to make highly toughened composites that show improved impact resistance.<ref>{{cite journal |last1=Quan |first1=Dong |last2=Bologna |first2=Francesca |last3=Scarselli |first3=Gennaro |last4=Ivankovic |first4=Alojz |last5=Murphy |first5=Neal |title=Interlaminar fracture toughness of aerospace-grade carbon fibre reinforced plastics interleaved with thermoplastic veils |journal=Composites Part A: Applied Science and Manufacturing |date=January 2020 |volume=128 |pages=105642 |doi=10.1016/j.compositesa.2019.105642 }}</ref> Another interesting aspect of such interleaved composites is that they are able to have shape memory behaviour without needing any [[shape-memory polymer]]s or [[shape-memory alloy]]s e.g. balsa plies interleaved with hot glue,<ref>{{cite book |doi=10.2514/6.2007-1717 |chapter=Morphing Structures by way of Stiffness Variations |title=48th AIAA/ASME/ASCE/AHS/ASC Structures, Structural Dynamics, and Materials Conference |date=2007 |last1=Gordon |first1=Benjamin |last2=Clark |first2=William |isbn=978-1-62410-013-0 }}</ref> aluminium plies interleaved with [[acrylate polymer|acrylic polymers]] or [[polyvinyl chloride|PVC]]<ref>{{cite journal |last1=Gandhi |first1=Farhan |last2=Kang |first2=Sang-Guk |title=Beams with controllable flexural stiffness |journal=Smart Materials and Structures |date=1 August 2007 |volume=16 |issue=4 |pages=1179–1184 |doi=10.1088/0964-1726/16/4/028 |bibcode=2007SMaS...16.1179G |hdl=10203/25282 |hdl-access=free }}</ref> and [[carbon-fiber-reinforced polymers|carbon-fiber-reinforced polymer]] laminates interleaved with [[polystyrene]].<ref>{{cite journal |last1=Robinson |first1=Paul |last2=Bismarck |first2=Alexander |last3=Zhang |first3=Bohao |last4=Maples |first4=Henry A. |title=Deployable, shape memory carbon fibre composites without shape memory constituents |journal=Composites Science and Technology |date=June 2017 |volume=145 |pages=96–104 |doi=10.1016/j.compscitech.2017.02.024 |hdl=10044/1/49550 |hdl-access=free }}</ref>

[[File:Glare honeycomb.jpg|thumb|Composite sandwich structure panel used for testing at NASA]]
A [[sandwich-structured composite]] is a special class of composite material that is fabricated by attaching two thin but stiff skins to a lightweight but thick core. The core material is normally low strength material, but its higher thickness provides the sandwich composite with high [[bending]] [[stiffness]] with overall low [[density]].<ref>{{cite web |title=What is a sandwich structure? |url=https://www.twi-global.com/technical-knowledge/faqs/faq-what-is-a-sandwich-structure.aspx |access-date=2020-12-17 |website=www.twi-global.com |language=en-GB |archive-date=2021-05-23 |archive-url=https://web.archive.org/web/20210523200354/https://www.twi-global.com/technical-knowledge/faqs/faq-what-is-a-sandwich-structure.aspx |url-status=live}}</ref><ref>{{cite web |title=Basics of sandwich technology |url=https://www.diabgroup.com/en-GB/Knowledge/Sandwich-technology/Basics-of-sandwich-technology |access-date=2020-12-17 |website=www.diabgroup.com |archive-date=2018-02-26 |archive-url=https://web.archive.org/web/20180226141624/https://www.diabgroup.com/en-GB/Knowledge/Sandwich-technology/Basics-of-sandwich-technology |url-status=dead}}</ref>

[[File:Spruce plywood.JPG|thumb|Plywood is used widely in construction]]
Wood is a naturally occurring composite comprising cellulose fibres in a [[lignin]] and [[hemicellulose]] matrix.<ref>{{cite web |date=2019-07-09 |title=Is Wood A Composite Material or A Pure Substance? |url=https://woodwoodland.com/is-wood-composite-material/ |access-date=2020-12-17 |website=WoodWoodLand |language=en-US |archive-date=2020-08-12 |archive-url=https://web.archive.org/web/20200812055100/https://woodwoodland.com/is-wood-composite-material/ |url-status=live}}</ref> [[Engineered wood]] includes a wide variety of different products such as wood fibre board, [[plywood]], [[oriented strand board]], [[wood plastic composite]] (recycled wood fibre in polyethylene matrix), [[Pykrete]] (sawdust in ice matrix), plastic-impregnated or [[plastic-coated paper|laminated paper]] or textiles, [[Arborite]], [[Formica (plastic)]], and [[Micarta]]. Other engineered laminate composites, such as [[Mallite]], use a central core of end grain [[balsa wood]], bonded to surface skins of light [[alloy]] or GRP. These generate low-weight, high rigidity materials.<ref>{{cite web |title=Composite wood; what is it? Origin and advantages |url=https://uk.silvadec.com/silvadec/history-of-composite-wood/ |access-date=2020-12-17 |website=Silvadec |language=en-US |archive-date=2017-12-01 |archive-url=https://web.archive.org/web/20171201054125/https://uk.silvadec.com/silvadec/history-of-composite-wood/ |url-status=dead}}</ref>

Particulate composites have particle as filler material dispersed in matrix, which may be nonmetal, such as glass, epoxy. Automobile tire is an example of particulate composite.<ref>{{cite book |doi=10.1016/B978-075067124-8/50001-1 |quote=A particulate composite is characterized as being composed of particles suspended in a matrix. Particles can have virtually any shape, size or configuration. Examples of well-known particulate composites are concrete and particle board. There are two subclasses of particulates: flake and filled/skeletal |chapter=Introduction to Composite Materials |title=Laminar Composites |date=1999 |last1=Staab |first1=George H. |pages=1–16 |isbn=978-0-7506-7124-8 }}</ref>

Advanced diamond-like carbon (DLC) coated polymer composites have been reported<ref name="ZiaShah2015">{{cite journal |last1=Zia |first1=Abdul Wasy |last2=Shah |first2=Atta Ur Rehman |last3=Lee |first3=Seunghun |last4=Song |first4=Jung Il |title=Development of diamond-like-carbon coated abaca-reinforced polyester composites for hydrophobic and outdoor structural applications |journal=Polymer Bulletin |volume=72 |issue=11 |year=2015 |pages=2797–2808 |doi=10.1007/s00289-015-1436-y }}</ref> where the coating increases the surface hydrophobicity, hardness and wear resistance.

Ferromagnetic composites, including those with a polymer matrix consisting, for example, of nanocrystalline filler of Fe-based powders and polymers matrix. Amorphous and nanocrystalline powders obtained, for example, from metallic glasses can be used. Their use makes it possible to obtain [[Ferromagnetism|ferromagnetic]] nanocomposites with controlled magnetic properties.<ref>{{cite journal |last1=Nowosielski |first1=Ryszard |last2=Gramatyka |first2=Paweł |last3=Sakiewicz |first3=Piotr |last4=Babilas |first4=Rafał |title=Ferromagnetic composites with polymer matrix consisted of nanocrystalline Fe-based filler |journal=Journal of Magnetism and Magnetic Materials |date=August 2015 |volume=387 |pages=179–185 |doi=10.1016/j.jmmm.2015.04.004 |bibcode=2015JMMM..387..179N }}</ref>