Materials science 1

Materials scienceFor one of the various publications named for the subject, see Materials Science and Engineering (journal).

Depiction of two "Fullerene Nano-gears" with multipleteeth.

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Materials science, also commonly known as materials engineering or materials science and engineering, is aninterdisciplinary field applying the properties of matter to various areas of science and engineering. This relativelynew scientific field investigates the relationship between the structure of materials at atomic or molecular scales andtheir macroscopic properties. It incorporates elements of applied physics and chemistry, with significant mediaattention focused on Nano science and nanotechnology. In recent years, materials science is becoming more widelyknown as a specific field of science and engineering. It is an important part of forensic engineering (Forensicengineering is the investigation of materials, products, structures or components that fail or do not operate orfunction as intended, causing personal injury or damage to property.) and failure analysis, the latter being the key tounderstanding, for example, the cause of various aviation accidents. Many of the most pressing scientific problemsthat are faced today are due to the limitations of the materials that are available and, as a result, breakthroughs in thisfield are likely to have a significant impact on the future of technology.

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HistoryMain article: History of materials scienceThe material of choice of a given era is often a defining point. Phrases such as Stone Age, Bronze Age, Iron Age,and Steel Age are great examples. Originally deriving from the manufacture of ceramics and its putative derivativemetallurgy, materials science is one of the oldest forms of engineering and applied science. Modern materialsscience evolved directly from metallurgy, which itself evolved from mining and (likely) ceramics and the use of fire.A major breakthrough in the understanding of materials occurred in the late 19th century, when the Americanscientist Josiah Willard Gibbs demonstrated that the thermodynamic properties related to atomic structure in variousphases are related to the physical properties of a material. Important elements of modern materials science are aproduct of the space race: the understanding and engineering of the metallic alloys, and silica and carbon materials,used in the construction of space vehicles enabling the exploration of space. Materials science has driven, and beendriven by, the development of revolutionary technologies such as plastics, semiconductors, and biomaterials.Before the 1960s (and in some cases decades after), many materials science departments were named metallurgydepartments, from a 19th and early 20th century emphasis on metals. The field has since broadened to include everyclass of materials, including ceramics, polymers, semiconductors, magnetic materials, medical implant materials,biological materials and nanomaterials (materiomics).

FundamentalsThe basis of materials science involves relating the desired properties and relative performance of a material in acertain application to the structure of the atoms and phases in that material through characterization. The majordeterminants of the structure of a material and thus of its properties are its constituent chemical elements and the wayin which it has been processed into its final form. These characteristics, taken together and related through the lawsof thermodynamics, govern a material’s microstructure, and thus its properties.The manufacture of a perfect crystal of a material is physically impossible. Instead materials scientists manipulatethe defects in crystalline materials such as precipitates, grain boundaries (Hall–Petch relationship), interstitial atoms,vacancies or substitutional atoms, to create materials with the desired properties.Not all materials have a regular crystal structure. Polymers display varying degrees of crystallinity, and many arecompletely non-crystalline. Glass as, some ceramics, and many natural materials are amorphous, not possessing anylong-range order in their atomic arrangements. The study of polymers combines elements of chemical and statisticalthermodynamics to give thermodynamic, as well as mechanical, descriptions of physical properties.In addition to industrial interest, materials science has gradually developed into a field which provides tests forcondensed matter or solid state theories. New physics emerge because of the diverse new material properties thatneed to be explained.

Materials in industryRadical materials advances can drive the creation of new products or even new industries, but stable industries alsoemploy materials scientists to make incremental improvements and troubleshoot issues with currently used materials.Industrial applications of materials science include materials design, cost-benefit tradeoffs in industrial production ofmaterials, processing techniques (casting, rolling, welding, ion implantation, crystal growth, thin-film deposition,sintering, glassblowing, etc.), and analytical techniques (characterization techniques such as electron microscopy,x-ray diffraction, calorimetry, nuclear microscopy (HEFIB), Rutherford backscattering, neutron diffraction,small-angle X-ray scattering (SAXS), etc.).Besides material characterization, the material scientist/engineer also deals with the extraction of materials and theirconversion into useful forms. Thus ingot casting, foundry techniques, blast furnace extraction, and electrolyticextraction are all part of the required knowledge of a metallurgist/engineer. Often the presence, absence or variation

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of minute quantities of secondary elements and compounds in a bulk material will have a great impact on the finalproperties of the materials produced, for instance, steels are classified based on 1/10 and 1/100 weight percentages ofthe carbon and other alloying elements they contain. Thus, the extraction and purification techniques employed inthe extraction of iron in the blast furnace will have an impact of the quality of steel that may be produced.The overlap between physics and materials science has led to the offshoot field of materials physics, which isconcerned with the physical properties of materials. The approach is generally more macroscopic and applied than incondensed matter physics. See important publications in materials physics for more details on this field of study.

Ceramics and glasses

Si3N4 ceramic bearing parts

Another application of the material sciences is the structures ofglass and ceramics, typically associated with the most brittlematerials. Bonding in ceramics and glasses use covalent andionic-covalent types with SiO2 (silica or sand) as a fundamentalbuilding block. Ceramics are as soft as clay and as hard as stoneand concrete. Usually, they are crystalline in form. Most glassescontain a metal oxide fused with silica. At high temperatures usedto prepare glass, the material is a viscous liquid. The structure ofglass forms into an amorphous state upon cooling. Windowpanesand eyeglasses are important examples. Fibers of glass are alsoavailable. Scratch resistant Corning Gorilla Glass is a well-knownexample of the application of materials science to drasticallyimprove the properties of common components. Diamond andcarbon in its graphite form are considered to be ceramics.

Engineering ceramics are known for their stiffness and stability under high temperatures, compression and electricalstress. Alumina, silicon carbide, and tungsten carbide are made from a fine powder of their constituents in a processof sintering with a binder. Hot pressing provides higher density material. Chemical vapor deposition can place a filmof a ceramic on another material. Cermets are ceramic particles containing some metals. The wear resistance of toolsis derived from cemented carbides with the metal phase of cobalt and nickel typically added to modify properties.

Composite materials

A 6 μm diameter carbon filament (running frombottom left to top right) siting atop the much larger

human hair.

Filaments are commonly used for reinforcement in compositematerials. Another application of material science in industry isthe making of composite materials. Composite materials arestructured materials composed of two or more macroscopicphases. Applications range from structural elements such assteel-reinforced concrete, to the thermally insulative tiles whichplay a key and integral role in NASA's Space Shuttle thermalprotection system which is used to protect the surface of theshuttle from the heat of re-entry into the Earth's atmosphere. Oneexample is reinforced Carbon-Carbon (RCC), the light graymaterial which withstands re-entry temperatures up to 1510 °C(2750 °F) and protects the Space Shuttle's wing leading edges and nose cap. RCC is a laminated composite materialmade from graphite rayon cloth and impregnated with a phenolic resin. After curing at high temperature in anautoclave, the laminate is pyrolized to convert the resin to carbon, impregnated with furfural alcohol in a vacuum

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chamber, and cured/pyrolized to convert the furfural alcohol to carbon. In order to provide oxidation resistance forreuse capability, the outer layers of the RCC are converted to silicon carbide.Other examples can be seen in the "plastic" casings of television sets, cell-phones and so on. These plastic casingsare usually a composite material made up of a thermoplastic matrix such as acrylonitrile-butadiene-styrene (ABS) inwhich calcium carbonate chalk, talc, glass fibers or carbon fibers have been added for added strength, bulk, orelectrostatic dispersion. These additions may be referred to as reinforcing fibers, or dispersants, depending on theirpurpose.

Polymers

Microstructure of part of a DNA double helixbiopolymer.

Polymers are also an important part of materials science. Polymersare the raw materials (the resins) used to make what we commonlycall plastics. Plastics are really the final product, created after oneor more polymers or additives have been added to a resin duringprocessing, which is then shaped into a final form. Polymers whichhave been around, and which are in current widespread use, includepolyethylene, polypropylene, PVC, polystyrene, nylons, polyesters,acrylics, polyurethanes, and polycarbonates. Plastics are generallyclassified as "commodity", "specialty" and "engineering" plastics.

PVC (polyvinyl-chloride) is widely used, inexpensive, and annualproduction quantities are large. It lends itself to an incredible arrayof applications, from artificial leather to electrical insulation andcabling, packaging and containers. Its fabrication and processingare simple and well-established. The versatility of PVC is due to thewide range of plasticisers and other additives that it accepts. Theterm "additives" in polymer science refers to the chemicals andcompounds added to the polymer base to modify its materialproperties.

Polycarbonate would be normally considered an engineering plastic(other examples include PEEK, ABS). Engineering plastics arevalued for their superior strengths and other special materialproperties. They are usually not used for disposable applications,unlike commodity plastics.

Specialty plastics are materials with unique characteristics, such as ultra-high strength, electrical conductivity,electro-fluorescence, high thermal stability, etc.The dividing lines between the various types of plastics is not based on material but rather on their properties andapplications. For instance, polyethylene (PE) is a cheap, low friction polymer commonly used to make disposableshopping bags and trash bags, and is considered a commodity plastic, whereas medium-density polyethylene(MDPE) is used for underground gas and water pipes, and another variety called Ultra-high Molecular WeightPolyethylene UHMWPE is an engineering plastic which is used extensively as the glide rails for industrialequipment and the low-friction socket in implanted hip joints.

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Metal alloysThe study of metal alloys is a significant part of materials science. Of all the metallic alloys in use today, the alloysof iron (steel, stainless steel, cast iron, tool steel, alloy steels) make up the largest proportion both by quantity andcommercial value. Iron alloyed with various proportions of carbon gives low, mid and high carbon steels. An ironcarbon alloy is only considered steel if the carbon level is between 0.01% and 2.00%. For the steels, the hardness andtensile strength of the steel is related to the amount of carbon present, with increasing carbon levels also leading tolower ductility and toughness. Heat treatment processes such as quenching and tempering can significantly changethese properties however. Cast Iron is defined as an iron–carbon alloy with more than 2.00% but less than 6.67%carbon. Stainless steel is defined as a regular steel alloy with greater than 10% by weight alloying content ofChromium. Nickel and Molybdenum are typically also found in stainless steels.Other significant metallic alloys are those of aluminium, titanium, copper and magnesium. Copper alloys have beenknown for a long time (since the Bronze Age), while the alloys of the other three metals have been relatively recentlydeveloped. Due to the chemical reactivity of these metals, the electrolytic extraction processes required were onlydeveloped relatively recently. The alloys of aluminium, titanium and magnesium are also known and valued for theirhigh strength-to-weight ratios and, in the case of magnesium, their ability to provide electromagnetic shielding.These materials are ideal for situations where high strength-to-weight ratios are more important than bulk cost, suchas in the aerospace industry and certain automotive engineering applications.

Sub-disciplines of materials scienceBelow is a list of disciplines within or related to the materials science field. These range from biomaterials, toceramics, to metals, to textile reinforced materials. Also note that these are linked to the respective main article.

• Biomaterials – materials that are derived from and/or used with life forms.• Ceramography – the study of the microstructures of high-temperature materials and refractories, including

structural ceramics such as RCC, polycrystalline silicon carbide and transformation toughened ceramics• Crystallography – the study of regular arrangement of atoms and ions in a solid, the defects associated with

crystal structures such as grain boundaries and dislocations, and the characterization of these structures andtheir relation to physical properties.

• Electronic and magnetic materials – materials such as semiconductors used to create integrated circuits,storage media, sensors, and other devices.

• Forensic engineering – the study of how products fail, and the vital role of the materials of construction• Forensic materials engineering – the study of material failure, and the light it sheds on how engineers specify

materials in their product• Glass science – any non-crystalline material including inorganic glasses, vitreous metals and non-oxide

glasses.• Materials characterization – such as diffraction with x-rays, electrons, or neutrons, and various forms of

spectroscopy and chemical analysis such as Raman spectroscopy, energy-dispersive spectroscopy (EDS),chromatography, thermal analysis, electron microscope analysis, etc., in order to understand and define theproperties of materials. See also List of surface analysis methods

• Metallography - Metallography is the study of the physical structure and components of metals, typically usingmicroscopy.

• Metallurgy – the study of metals and their alloys, including their extraction, microstructure and processing.• Microtechnology – study of materials and processes and their interaction, allowing microfabrication of

structures of micrometric dimensions, such as Microelectromechanical systems (MEMS).• Nanotechnology – rigorously, the study of materials where the effects of quantum confinement, the

Gibbs–Thomson effect, or any other effect only present at the nanoscale is the defining property of the material; but more commonly, it is the creation and study of materials whose defining structural properties are

Materials science 6

anywhere from less than a nanometer to one hundred nanometers in scale, such as molecularly engineeredmaterials.

• Rheology – Some practitioners consider rheology a sub-field of materials science, because it can cover anymaterial that flows. However, modern rheology typically deals with non-Newtonian fluid dynamics, so it isoften considered a sub-field of continuum mechanics. See also granular material.

• Surface science/catalysis – interactions and structures between solid-gas solid-liquid or solid-solid interfaces.• Textile reinforced materials – materials in the form of ceramic or concrete are reinforced with a primarily

woven or non-woven textile structure to impose high strength with comparatively more flexibility to withstandvibrations and sudden jerks.

• Tribology – the study of the wear of materials due to friction and other factors.

Methods, processes, and related topicsBelow are links to topics that explain methods, processes and related topics in order to enhance understanding ofmaterials science.

• Alloying, corrosion, and thermal or mechanical processing, for a specialized treatment of metallurgicalmaterials—with applications ranging from aerospace and industrial equipment to the civil industries

• Biomaterials, physiology, biomechanics, biochemistry, for a specialized understanding of how materialsintegrate into biological systems, e.g., through materiomics

• Crystallography, quantum chemistry or quantum physics, for the structure (symmetry and defects) and bondingin materials (e.g., ionic, metallic, covalent, and van der Waals bonding)

• Diffraction and wave mechanics, for the science behind characterization systems, e.g., X-ray diffraction(XRD) transmission electron microscopy (TEM)

• Electronic properties of materials, and solid-state physics, for the understanding of the electronic, thermal,magnetic, and optical properties of materials

• Mechanical behavior of materials, to understand the mechanical properties of materials, defects and theirpropagation, and their behavior under static, dynamic, and cyclic loads

• Phase transformation kinetics, for the kinetics of phase transformations (with particular emphasis onsolid-solid phase transitions)

• Polymer properties, synthesis, and characterization, for a specialized understanding of how polymers behave,how they are made, and how they are characterized; exciting applications of polymers include liquid crystaldisplays (LCDs, the displays found in most cell phones, cameras, and iPods), novel photovoltaic devices basedon semiconductor polymers (which, unlike the traditional silicon solar panels, are flexible and cheap tomanufacture, albeit with lower efficiency), and membranes for room-temperature fuel cells (as protonexchange membranes) and filtration systems in the environmental and biomedical fields

• Semiconductor materials and semiconductor devices, for a specialized understanding of the advancedprocesses used in industry (e.g. crystal growth techniques, thin-film deposition, ion implantation,photolithography), their properties, and their integration in electronic devices

• Solid-state physics is the study of rigid matter, or solids, through methods such as quantum mechanics,crystallography, electromagnetism, and metallurgy. It is the largest branch of condensed matter physics.Solid-state physics studies how the large-scale properties of solid materials result from their atomic-scaleproperties. Thus, solid-state physics forms the theoretical basis of materials science. It also has directapplications, for example in the technology of transistors and semiconductors.

• Thermodynamics, statistical mechanics, and physical chemistry, for phase equilibrium conditions, phasediagrams of materials systems (multi-phase, multi-component, reacting and non-reacting systems)

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References[1] http:/ / en. wikipedia. org/ w/ index. php?title=Template:Science& action=edit

Bibliography• Ashby, Michael; Hugh Shercliff; David Cebon (2007). Materials: engineering, science, processing and design

(1st ed.). Butterworth-Heinemann. ISBN 978-0-7506-8391-3.• Askeland, Donald R.; Pradeep P. Phulé (2005). The Science & Engineering of Materials (5th ed.).

Thomson-Engineering. ISBN 0-534-55396-6.• Callister, Jr., William D. (2000). Materials Science and Engineering – An Introduction (5th ed.). John Wiley and

Sons. ISBN 0-471-32013-7.• Eberhart, Mark (2003). Why Things Break: Understanding the World by the Way It Comes Apart. Harmony.

ISBN 1-4000-4760-9.• Gaskell, David R. (1995). Introduction to the Thermodynamics of Materials (4th ed.). Taylor and Francis

Publishing. ISBN 1-56032-992-0.• Gordon, James Edward (1984). The New Science of Strong Materials or Why You Don't Fall Through the Floor

(eissue ed.). Princeton University Press. ISBN 0-691-02380-8.• Mathews, F.L. & Rawlings, R.D. (1999). Composite Materials: Engineering and Science. Boca Raton: CRC

Press. ISBN 0-8493-0621-3.• Lewis, P.R., Reynolds, K. & Gagg, C. (2003). Forensic Materials Engineering: Case Studies. Boca Raton: CRC

Press.• Wachtman, John B. (1996). Mechanical Properties of Ceramics. New York: Wiley-Interscience, John Wiley &

Son's. ISBN 0-471-13316-7.• Walker, P., ed. (1993). Chambers Dictionary of Materials Science and Technology. Chambers Publishing.

ISBN 0-550-13249-X.

Further reading• Timeline of Materials Science (http:/ / www. materialmoments. org/ top100. html) at The Minerals, Metals &

Materials Society (TMS) – Accessed March 2007• Burns, G.; Glazer, A.M. (1990). Space Groups for Scientists and Engineers (2nd ed.). Boston: Academic Press,

Inc. ISBN 0-12-145761-3.• Cullity, B.D. (1978). Elements of X-Ray Diffraction (2nd ed.). Reading, Massachusetts: Addison-Wesley

Publishing Company. ISBN 0-534-55396-6.• Giacovazzo, C; Monaco HL; Viterbo D; Scordari F; Gilli G; Zanotti G; Catti M (1992). Fundamentals of

Crystallography. Oxford: Oxford University Press. ISBN 0-19-855578-4.• Green, D.J.; Hannink, R.; Swain, M.V. (1989). Transformation Toughening of Ceramics. Boca Raton: CRC Press.

ISBN 0-8493-6594-5.• Lovesey, S. W. (1984). Theory of Neutron Scattering from Condensed Matter; Volume 1: Neutron Scattering.

Oxford: Clarendon Press. ISBN 0-19-852015-8.• Lovesey, S. W. (1984). Theory of Neutron Scattering from Condensed Matter; Volume 2: Condensed Matter.

Oxford: Clarendon Press. ISBN 0-19-852017-4.• O'Keeffe, M.; Hyde, B.G. (1996). Crystal Structures; I. Patterns and Symmetry. Washington, DC: Mineralogical

Society of America, Monograph Series. ISBN 0-939950-40-5.• Squires, G.L. (1996). Introduction to the Theory of Thermal Neutron Scattering (2nd ed.). Mineola, New York:

Dover Publications Inc. ISBN 0-486-69447-X.• Young, R.A., ed. (1993). The Rietveld Method. Oxford: Oxford University Press & International Union of

Crystallography. ISBN 0-19-855577-6.

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External links• Materials Knowledge Transfer Network (https:/ / connect. innovateuk. org/ web/ materialsktn/ overview)• Material Measurement Laboratory, NIST (http:/ / www. nist. gov/ mml/ )• SubsTech (Substances & Technologies) (http:/ / www. substech. com/ )• Nanoscale Interdisciplinary Research Team (http:/ / nirt. pa. msu. edu/ )• CMR – Centre for Materials Research (http:/ / cmr. curtin. edu. au/ )• Materials Science and Engineering (https:/ / inlportal. inl. gov/ portal/ server. pt?open=514& objID=1650&

parentname=CommunityPage& parentid=7& mode=2& in_hi_userid=200& cached=true) – Idaho NationalLaboratory

• Dissemination of IT for the Promotion of Materials Science (DoITPoMS) (http:/ / www. doitpoms. ac. uk/ tlplib/index. php)

• EURELNET Technology Transfer Department at the University of Bordeaux (https:/ / www. eurelnet. org/ )• MATTER (Materials e-Learning Resources) at the University of Liverpool (http:/ / www. matter. org. uk/ )• CORE-Materials Open Educational Resources for Materials Science & Engineering (http:/ / core. materials. ac.

uk/ )• Materials Research CEIT Research Institute (http:/ / www. ceit. es/ index. php?option=com_content&

view=article& id=25& Itemid=28& lang=en)• Manufacturing engineering and mechanical properties of plastic parts (http:/ / www3. fi. mdp. edu. ar/

ingpolimeros/ en/ ) – INTEMA (Research Institute), Universidad Nacional de Mar del Plata – CONICET• Razi Metallurgical Research Center, RMRC (http:/ / www. razi-center. net/ )• Engineering Materials, Engineers Edge (http:/ / www. engineersedge. com/ manufacturing_menu. shtml)

Professional organizations• Materials Research Society, MRS (http:/ / www. mrs. org/ home/ )• European Materials Research Society, EMRS (http:/ / www. emrs-strasbourg. com/ )• ASM International (http:/ / asmcommunity. asminternational. org/ portal/ site/ www/ )• The Minerals, Metals, & Materials Society, TMS (http:/ / www. tms. org/ TMSHome. aspx)• Materials Australia (http:/ / www. materialsaustralia. com. au/ )• American Ceramic Society, ACerS (http:/ / www. ceramics. org/ index. aspx)• NACE International (http:/ / www. nace. org/ )• The American Institute of Mining, Metallurgical, and Petroleum Engineers, AIME (http:/ / www. aimehq. org/ )• Society for the Advancement of Material and Process Engineering, SAMPE (http:/ / www. sampe. org/ )• The Institute of Materials, Minerals and Mining, IOM3 (http:/ / www. iom3. org/ )• Alpha Sigma Mu, ΑΣΜ (http:/ / www. alphasigmamu. org/ )• Central European Institute of Technology, CEITEC (http:/ / www. ceitec. eu/ )• Association for Iron and Steel Technology, AIST (http:/ / www. aist. org/ )• Federation of European Materials Societies, FEMS (http:/ / www. fems. org/ )• Ceramic Research Centre Inc. at Turkey, SAM (http:/ / www. seramikarastirma. com. tr/ en/ )• National Nanotechnology Research Centre at Turkey, UNAM (http:/ / www. nano. org. tr/ index1. html)• Chamber of Metallurgical Engineers of Turkey, UCTEA CME (http:/ / www. metalurji. org. tr)

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International conferences• 2013 MRS Fall Meeting (http:/ / www. mrs. org/ fall2013/ )• 2013 MRS Spring Meeting (http:/ / www. mrs. org/ spring2013/ )• TMS 2012 Annual Meeting & Exhibition (http:/ / www. isbb2011. com/ )• 16th International Metallurgy & Materials Congress, IMMC2012 (http:/ / www. metalurji. org. tr/ IMMC2012/

e_index. html)• 17th International Symposium on Boron, Borides and Related Material (http:/ / www. isbb2011. com/ )• International Ceramic, Glass, Porcelain Enamel, Glaze and Pigment, SERES (http:/ / seres. anadolu. edu. tr/ en/ )

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Article Sources and ContributorsMaterials science  Source: http://en.wikipedia.org/w/index.php?oldid=606869752  Contributors: 100110100, A13ean, APH, Abraham70, AdventurousSquirrel, Afluegel, Aforsy, Agogino,Ahoerstemeier, Alansohn, Ale jrb, Alexf, Alexnye, Alperen, Amgreen, Antarsaeed, ArglebargleIV, Arnoutf, Awmarcz, Babbler, BeaumontTaz, Ben Ben, Bensaccount, Bmeguru, Bob, Bobrayner,Borgx, Bos7, Brian the Editor, Bryan Derksen, Bugtrio, Bunnyhop11, Bus stop, CJeynes, CapFan, Carol Newby, Cbdorsett, Ceramres, Chateau Brillant, Chemater, ChrisGualtieri, Christian75,Coffeenutter, Commander Keane, Conversion script, Conwiktion, Core-materials, Cquan, Cribananda, Croat Canuck, Cstras, Cutler, Czamani, DARTH SIDIOUS 2, DVdm, Dan Guan, DanHunter, Daniel dulay, Daniele Pugliesi, DavidLevinson, Dawn Bard, Denisarona, Dflanagan, Dhatfield, Dia^, Dinodeck1, Doom, Doulos Christos, Dr Sumeet, DrMikeF, ESkog, Eastlaw, Edward,Emperorbma, Enirac Sum, Erik Holladay, Erodium, EuroCarGT, Extraordinary, FJPB, Fahlmanb, Faizan, Falcon8765, Fatiguehop, Ferengi, Flyer22, France3470, Francis barin, Freecat,Frigaardj, Gaius Cornelius, Gamewizard71, Gareth Griffith-Jones, Gentgeen, Geologyguy, Giftlite, Gonzonoir, Gorthian, Graham87, Grey Shadow, Greyhood, Ground Zero, H.d.l., Haenaroad,Hankwang, Hdroute, Herbert Chang, Hike395, His Manliness, Hourahine, Hulagutten, Hurricane111, Hydro, Ian.thomson, Icairns, Iepeulas, Ike9898, Imecs, Incompetence, InsufficientData,Iohannes Animosus, Iridescent, Itamblyn, J.delanoy, JHCaufield, Ja 62, JamesBWatson, Jamietw, Jdtyler, Jeff G., Jesse V., Jim1138, JinJian, Jjroftms, Jntf, Jr1038, Jusdafax, Jweiss11,Karl-Henner, Karnesky, Karol Langner, Karthikc123, Kdliss, Kierkkadon, Kyng, Lacomj, Lamro, Ld. Ata, Ld100, Leszek Jańczuk, Levineps, Logger9, Looscan, Looxix, Lotje, LouScheffer,Lukegillenwater, Lumos3, M stone, MKar, MOD1976, Magioladitis, Makecat, Makyen, Marj Tiefert, Mark Arsten, Matador, Materialscientist, Maurreen, Mausy5043, Mayumashu, Mboverload,Mdd, Mean as custard, Meegs, Megaman en m, MelbourneStar, Merit 2, Mic, Michael Hardy, Mileystudy, Mileytenway, Minimac, Mpeisenbr, Mrba70, Mtd074, Murray.booth, NanoTy, Naraht,New Light Taiwan, Northamerica1000, ODS40, Oleg Alexandrov, Olof, Orientalknight, OverlordQ, P99am, Pdcook, Peter atheist, Peteranderson6663, Peterlewis, Phasmatisnox, Phil the, PhilipTrueman, Philly jawn, Physchim62, Piano non troppo, Pinethicket, Polyparadigm, Possum, Rebroad, Remux, Rexkut, Rifleman 82, Riot-Wolf, Rjwilmsi, Robert Cothern, Robinh, Rod57, Rogerwilbury, Romaioi, RosaWeber, Runewiki777, S mundi, SA mtm, Sammo, Satellizer, SchreyP, Scullin, SebastianHelm, SeventyThree, Shanel, SheffieldSteel, Shemurgar, Shmuel, Sietse Snel,Silly rabbit, Siroxo, Skizzik, Slicky, SmoJoe, Smus, SnapRat, Someguy1221, SouthLake, Squids and Chips, Srleffler, Stardust8212, Steve Quinn, Sthubertus, SudhirP, Suva, TVBZ28, TalonArtaine, Techman224, Template namespace initialisation script, Teukros, Tgx, The High Fin Sperm Whale, The Thing That Should Not Be, The undertow, The wub, TheFeds, Themonuk,Theodoreroosevelt2005, Thetrolol9, Thumperward, Tide rolls, Tim teddybear, Tkgnamboodhiri, Tom harrison, Tommy2010, Tonigm, Trent 900, Turtledove556, Twisp, TwistOfCain,Tyronjesper, TysK, Umadforbbw, Uriah923, V8rik, Versageek, Versus22, Vinodhchennu, Vsmith, Wavelength, Wayiti lukas, Weihao.chiu, Welsh, Whisky drinker, Wizard191, Wjbssb, Wnzrf,WojPob, Woohookitty, Wtshymanski, Wyatt915, Yintan, Yk Yk Yk, You Gillespie, Yousuf usama, YusrSehl, Zedshort, Zhigangsuo, Воображение, 500 ,א.שטיימן anonymous edits

Image Sources, Licenses and ContributorsImage:Fullerene Nanogears - GPN-2000-001535.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:Fullerene_Nanogears_-_GPN-2000-001535.jpg  License: Public Domain Contributors: NASAImage:Si3N4bearings.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:Si3N4bearings.jpg  License: Public Domain  Contributors: David W. Richerson and Douglas W. Freitag; OakRidge National Laboratory (federal lab.)File:Cfaser haarrp.jpg  Source: http://en.wikipedia.org/w/index.php?title=File:Cfaser_haarrp.jpg  License: Creative Commons Attribution-ShareAlike 3.0 Unported  Contributors: Anton,SaperaudImage:ADN animation.gif  Source: http://en.wikipedia.org/w/index.php?title=File:ADN_animation.gif  License: Public Domain  Contributors: brian0918�

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