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Depiction of two "Fullerene Nano-gears" with multiple teeth.

Materials science is an interdisciplinary field applying the properties of matter to various areas of science and engineering. This scientific field investigates the relationship between the structure of materials at atomic or molecular scales and their macroscopic properties. It incorporates elements of applied physics and chemistry. With significant media attention focused on nanoscience and nanotechnology in recent years, materials science has been propelled to the forefront at many universities. It is also an important part of forensic engineering and failure analysis. Materials science also deals with fundamental properties and characteristics of materials.

History[link]

The material of choice of a given era is often a defining point. Phrases such as Stone Age, Bronze Age, and Steel Age are good examples. Originally deriving from the manufacture of ceramics and its putative derivative metallurgy, materials science is one of the oldest forms of engineering and applied science. Modern materials science 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 American scientist Josiah Willard Gibbs demonstrated that the thermodynamic properties related to atomic structure in various phases are related to the physical properties of a material. Important elements of modern materials science are a product 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 been driven 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 metallurgy departments, from a 19th and early 20th century emphasis on metals. The field has since broadened to include every class of materials, including ceramics, polymers, semiconductors, magnetic materials, medical implant materials and biological materials (materiomics).

Fundamentals[link]

The basis of materials science involves relating the desired properties and relative performance of a material in a certain application to the structure of the atoms and phases in that material through characterization. The major determinants of the structure of a material and thus of its properties are its constituent chemical elements and the way in which it has been processed into its final form. These characteristics, taken together and related through the laws of thermodynamics, govern a material’s microstructure, and thus its properties.

The manufacture of a perfect crystal of a material is currently physically impossible. Instead materials scientists manipulate the 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 are completely non-crystalline. Glasses, some ceramics, and many natural materials are amorphous, not possessing any long-range order in their atomic arrangements. The study of polymers combines elements of chemical and statistical thermodynamics 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 for condensed matter or solid state theories. New physics emerge because of the diverse new material properties which need to be explained.

Classes of materials[link]

Materials science encompasses various classes of materials, each of which may constitute a separate field. There are several ways to classify materials. For instance by the type of bonding between the atoms. The traditional groups are ceramics, metals and polymers based on atomic structure and chemical composition. New materials has resulted in more classes.^[1] One way of classifying materials is:

• Biomaterials
• Carbon
• Ceramics
• Composite materials
• Glass
• Metals
• Nano materials
• Polymers
• Refractory
• Semiconductors
• Thin Films
• Functionally Graded Materials.

Materials in industry[link]

Radical materials advances can drive the creation of new products or even new industries, but stable industries also employ 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 of materials, 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 their conversion into useful forms. Thus ingot casting, foundry techniques, blast furnace extraction, and electrolytic extraction are all part of the required knowledge of a metallurgist/engineer. Often the presence, absence or variation of minute quantities of secondary elements and compounds in a bulk material will have a great impact on the final properties of the materials produced, for instance, steels are classified based on 1/10 and 1/100 weight percentages of the carbon and other alloying elements they contain. Thus, the extraction and purification techniques employed in the 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 is concerned with the physical properties of materials. The approach is generally more macroscopic and applied than in condensed matter physics. See important publications in materials physics for more details on this field of study.

Ceramics and glasses[link]

Si₃N₄ ceramic bearing parts

Another application of the material sciences is the structures of glass and ceramics, typically associated with the most brittle materials. Bonding in ceramics and glasses are using covalent and ionic-covalent types with SiO₂ (silica or sand) as a fundamental building block. Ceramics are as soft as clay and as hard as stone and concrete. Usually, they are crystalline in form. Most glasses contain a metal oxide fused with silica. At high temperatures used to prepare glass, the material is a viscous liquid. The structure of glass forms into an amorphous state upon cooling. Windowpanes and eyeglasses are important examples. Fibers of glass are also available. Diamond and carbon in its graphite form are considered to be ceramics.

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

Composite materials[link]

A 6 μm diameter carbon filament (running from bottom left to top right) compared to a human hair.

filaments is commonly used for reinforcement in composite materials.

Another application of material science in industry is the making of composite materials. Composite materials are structured materials composed of two or more macroscopic phases. Applications range from structural elements such as steel-reinforced concrete, to the thermally insulative tiles which play a key and integral role in NASA's Space Shuttle thermal protection system which is used to protect the surface of the shuttle from the heat of re-entry into the Earth's atmosphere. One example is reinforced Carbon-Carbon (RCC), The light gray material 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 material made from graphite rayon cloth and impregnated with a phenolic resin. After curing at high temperature in an autoclave, the laminate is pyrolized to convert the resin to carbon, impregnated with furfural alcohol in a vacuum chamber, and cured/pyrolized to convert the furfural alcohol to carbon. In order to provide oxidation resistance for reuse 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 casings are usually a composite material made up of a thermoplastic matrix such as acrylonitrile-butadiene-styrene (ABS) in which calcium carbonate chalk, talc, glass fibers or carbon fibers have been added for added strength, bulk, or electrostatic dispersion. These additions may be referred to as reinforcing fibers, or dispersants, depending on their purpose.

Polymers[link]

Microstructure of part of a DNA double helix biopolymer.

Polymers are also an important part of materials science. Polymers are the raw materials (the resins) used to make what we commonly call plastics. Plastics are really the final product, created after one or more polymers or additives have been added to a resin during processing, which is then shaped into a final form. Polymers which have been around, and which are in current widespread use, include polyethylene, polypropylene, PVC, polystyrene, nylons, polyesters, acrylics, polyurethanes, and polycarbonates. Plastics are generally classified as "commodity", "specialty" and "engineering" plastics.

PVC (polyvinyl-chloride) is widely used, inexpensive, and annual production quantities are large. It lends itself to an incredible array of applications, from artificial leather to electrical insulation and cabling, packaging and containers. Its fabrication and processing are simple and well-established. The versatility of PVC is due to the wide range of plasticisers and other additives that it accepts. The term "additives" in polymer science refers to the chemicals and compounds added to the polymer base to modify its material properties.

Polycarbonate would be normally considered an engineering plastic (other examples include PEEK, ABS). Engineering plastics are valued for their superior strengths and other special material properties. 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 and applications. For instance, polyethylene (PE) is a cheap, low friction polymer commonly used to make disposable shopping 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 Weight Polyethylene UHMWPE is an engineering plastic which is used extensively as the glide rails for industrial equipment and the low-friction socket in implanted hip joints.

Metal alloys[link]

The study of metal alloys is a significant part of materials science. Of all the metallic alloys in use today, the alloys of iron (steel, stainless steel, cast iron, tool steel, alloy steels) make up the largest proportion both by quantity and commercial value. Iron alloyed with various proportions of carbon gives low, mid and high carbon steels. An iron carbon alloy is only considered steel if the carbon level is between 0.01% and 2.00%. For the steels, the hardness and tensile strength of the steel is related to the amount of carbon present, with increasing carbon levels also leading to lower ductility and toughness. Heat treatment processes such as quenching and tempering can significantly change these 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 of Chromium. 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 been known for a long time (since the Bronze Age), while the alloys of the other three metals have been relatively recently developed. Due to the chemical reactivity of these metals, the electrolytic extraction processes required were only developed relatively recently. The alloys of aluminium, titanium and magnesium are also known and valued for their high 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, such as in the aerospace industry and certain automotive engineering applications.

Digital materials[link]

This section may be confusing or unclear to readers. Please help clarify the section; suggestions may be found on the talk page. (February 2012)

Digital Materials (DMs) are engineered materials manufactured from two or more different constituent materials, according to a digitally encoded three dimensional (3D) phase structure design (the DM code), and produced by an additive manufacturing (AM) process.^[2]

• 

  Figure 1: A schematic representation of a rasterized 3D object (stapler) showing voxels made of a single constituent material

• 

  Figure 2: A schematic representation of a rasterized 3D object (stapler) showing voxels made of two different constituent materials

• 

  Figure 3: Schematic representation of the cross section of an Isotropic DM

In DMs the constituent materials are combined together at a voxel level (figures 1-3) to create domains or phases with significantly different physical or chemical properties which remain separate and distinct at the macroscopic or microscopic scale within the finished DM structure. Hierarchical structures in which macro voxels are created from more than one constituent material are also possible.

DMs can be divided into two main categories: Isotropic and Anisotropic DMs.

Isotropic DMs[link]

In this type of DM, the constituent materials are combined homogeneously as for example, a non-continuous phase made of constituent material “a” randomly “dispersed” within a continuous phase made of constituent material “b” (figure 3). A uniform combination between constituent materials, or a mix of uniform and random combinations are also possible. The combination of constituent materials can be at the single voxel level as in figure 3, but may also be at higher level as for example a number of voxels as the minimum amount of one constituent material.

Anisotropic DMs[link]

These types of DMs have an anisotropic 3D phase structure design, and therefore anisotropic properties along different axis within a single object (figure 4).

Figure 4: Example of anisotropic DM phase structure design

Anisotropic DMs may also be Geometry Dependent; in this type of DM there is a “dialog” between the object design and the DM code, which results in different constituent material arrangements in different object designs, or in different regions within a single object. In Geometry Dependent DMs the DM code is responsible for defining the rules that govern the DM composition as a function of a respective object geometry and size; analogous to the way the genetic code in living organisms is responsible for dictating the characteristics of a living organism. The DM code defining a Geometry Dependent DM comprises a set of rules or algorithms that when applied to the manufacturing of a specific object, permits allocating constituent materials in different object regions, according to the specific object design. Thus, in Geometry Dependent DMs, the DM is not be produced for subsequent use in the manufacture of a desired object; rather the DM production process and the object manufacturing process are one.

An example of a Geometry Dependent DM code algorithm is presented here:

1. Two constituent materials: A and B
2. The object is made of constituent material A in all object regions besides those defined as made of constituent material B
3. Constituent material B is used to form as 1mm deep region comprising the outer surface of the object

In this example, every object region having a thickness of 2mm or less, is produced solely from constituent material B, while object regions thicker than 2mm are constructed of two regions, an outermost region of 1mm in thickness made of constituent material B and a core made of constituent material A.

Figure 5: A schematic representation of the cross section of a Geometry Dependent DM comprising two different constituent materials; constituent material B in yellow and constituent material A in red.

Geometry Dependent DMs can be further divided into two subcategories: Step DMs and Graded DMs. While in Step DMs constituent materials are combined in substantially well-defined phases, as shown in figure 5, in Graded DMs the DM composition varies gradually along at least one defined trajectory or axis of an object, in a graded fashion. An example of a Graded DM is one in which the DM composition on one side of the object is substantially richer in one constituent material than another, while on other side of the object, the DM composition is substantially richer in the other constituent material, and where the content ratio between the constituent materials gradually varies from one side of the object to the other.

There is also the possibility of Geometry Dependent DMs having Step as well as Graded characteristics within a single object.

Digital materials research[link]

Different aspects in the field of DMs have recently been the focus of intensive research, in the industrial sector as well as in the academic sector. According to Mary C. Boyce et al.,^[3] co-continuous glassy polymer/rubbery materials with sub-millimeter feature size, fabricated using a 3D printer, expose enhancements in stiffness, strength and energy dissipation. According to Mary C. Boyce, “geometric and topological arrangement of the constituent materials provides avenues to engineer the macroscale material properties”.

A data-driven process for designing and fabricating materials with desired deformation behavior has been reported.^[4] According to this report, “an optimization process that finds the best combination of stacked layers that meets a user’s criteria specified by example deformations” has been developed. In this study, and in order to demonstrate the optimization process validity, objects with complex heterogeneous materials were fabricated using a modern multi-material 3D printer.

In another study,^[5] “a complete pipeline for measuring, modeling, and fabricating objects with specified subsurface scattering behaviors” was proposed. According to the authors, the process was validated by producing homogeneous and heterogeneous materials using a multi-material 3D printer.

Neri Oxman ^[6] takes nature as a model, and proposes what she calls “Variable Property Design (VPD)”, as a method for design, in which “material assemblies are modeled, simulated and fabricated with varying properties”, in order to give an answer to functional constraints. Oxman's Variable Property Rapid Prototyping approach aims at integrating between material properties and environmental constraints within the computational modeling environment and as part of the form-generation and fabrication process.^[7]

Hod Lipson et al. ^[8] has reported the simulation of materials properties as a function of their “digital material” composition. According to this report, properties as stiffness, CTE, and failure modes were obtained by varying voxel manufacturing precision, the percentage of randomly distributed constituent materials, and the voxel microstructure. Furthermore, it has been stated by the authors that material properties may be tuned anywhere between the respective properties of two constituent materials, by simple randomly halftone a percentage constituent materials. In addition, properties such as stiffness or negative Poisson's ratio, has been reported to be obtained using relatively dense common materials, by the inclusion of a hierarchical voxel microstructure.

Overview[link]

• Biomaterials – materials that are derived from and/or used with biological systems.
• 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 how atoms in a solid fill space, the defects associated with crystal structures such as grain boundaries and dislocations, and the characterization of these structures and their 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 the properties of materials. See also List of surface analysis methods
• Metallography - Metallography is the study of the physical structure and components of metals, typically using microscopy.
• 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 anywhere from less than a nanometer to one hundred nanometers in scale, such as molecularly engineered materials.
• 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 withstand vibrations and sudden jerks.

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

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

Primary topics[link]

• Alloying, corrosion, and thermal or mechanical processing, for a specialized treatment of metallurgical materials—with applications ranging from aerospace and industrial equipment to the civil industries
• Biomaterials, physiology, biomechanics, biochemistry, for a specialized understanding of how materials integrate into biological systems, e.g., through materiomics
• Crystallography, quantum chemistry or quantum physics, for the structure (symmetry and defects) and bonding in 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 their propagation, and their behavior under static, dynamic, and cyclic loads
• Phase transformation kinetics, for the kinetics of phase transformations (with particular emphasis on solid-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 crystal displays (LCDs, the displays found in most cell phones, cameras, and iPods), novel photovoltaic devices based on semiconductor polymers (which, unlike the traditional silicon solar panels, are flexible and cheap to manufacture, albeit with lower efficiency), and membranes for room-temperature fuel cells (as proton exchange membranes) and filtration systems in the environmental and biomedical fields
• Semiconductor materials and semiconductor devices, for a specialized understanding of the advanced processes 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-scale properties. Thus, solid-state physics forms the theoretical basis of materials science. It also has direct applications, for example in the technology of transistors and semiconductors.
• Thermodynamics, statistical mechanics, and physical chemistry, for phase equilibrium conditions, phase diagrams of materials systems (multi-phase, multi-component, reacting and non-reacting systems)
• Transport phenomena for the transport of heat, mass, and momentum in materials processing.

Professional organizations[link]

• Materials Research Society, MRS
• European Materials Research Society, EMRS
• ASM International
• The Minerals, Metals, & Materials Society, TMS
• Materials Australia
• American Ceramic Society, ACerS
• NACE International
• The American Institute of Mining, Metallurgical, and Petroleum Engineers, AIME
• Society for the Advancement of Material and Process Engineering, SAMPE
• The Institute of Materials, Minerals and Mining, IOM³
• Alpha Sigma Mu, ΑΣΜ
• Central European Institute of Technology, CEITEC
• Association for Iron and Steel Technology, AIST
• Federation of European Materials Societies, FEMS
• Ceramic Research Centre Inc. at Turkey, SAM
• National Nanotechnology Research Centre at Turkey, UNAM
• Chamber of Metallurgical Engineers of Turkey, UCTEA CME

International conferences[link]

• 2012 MRS Spring Meeting
• TMS 2012 Annual Meeting & Exhibition
• 16th International Metallurgy & Materials Congress, IMMC2012
• 17th International Symposium on Boron, Borides and Related Material
• International Ceramic, Glass, Porcelain Enamel, Glaze and Pigment, SERES
• Conference and Expo on Material Science and Engineering

See also[link]

Bibliography[link]

• Ashby, Michael; Hugh Shercliff and 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 [[Special:BookSources/0-8493-0621-7|0-8493-0621-7]]. 
• 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[link]

• Timeline of Materials Science 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, and 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. 

References[link]

1. ^ Callister, William (2007). Materials Science and Engineering - An Introduction. United States of America: John Wiley & Sons, Inc.. pp. 5–13. ISBN 978-0-471-73696-7. 
2. ^ Eduardo Napadensky, The Hebrew University of Jerusalem
3. ^ Co-Continuous Composite Materials for Stiffness, Strength, and Energy Dissipation, Lifeng Wang , Jacky Lau , Edwin L. Thomas, and Mary C. Boyce *, Adv. Mater. 2011, 23, 1524–1529.
4. ^ Design and Fabrication of Materials with Desired Deformation Behavior, B. Bickel, M. Bächer, M. A. Otaduy, H. R. Lee, H. Pfister, M. Gross, W. Matusik, Proceedings of ACM SIGGRAPH (Los Angeles, USA, July 25–29, 2010), ACM Transactions on Graphics, vol. 29, no. 4.
5. ^ Physical Reproduction of Materials with Specified Subsurface Scattering, Miloš Hašan, Martin Fuchs, Wojciech Matusik, Hanspeter Pfister, Szymon Rusinkiewicz, ACM Transactions on Graphics (Proc. SIGGRAPH), August 2010.
6. ^ Structuring Materiality: Design Fabrication of Heterogeneous Materials Neri Oxman (2010), Architectural Design 80 (4) p. 78–85
7. ^ Neri Oxman (2011): Variable property rapid prototyping, Virtual and Physical Prototyping, 6:1, 3-31
8. ^ Tunable digital material properties for 3D voxel printers, Jonathan Hiller, Hod Lipson, (2010), Rapid Prototyping Journal, Vol. 16 Iss: 4, pp.241 – 247

External links[link]

Wikimedia Commons has media related to: Materials science

Wikibooks has a book on the topic of Materials Science

• Nanoscale Interdisciplinary Research Team
• CMR – Centre for Materials Research
• Materials Science and Engineering – Idaho National Laboratory
• Dissemination of IT for the Promotion of Materials Science (DoITPoMS)
• EURELNET Technology Transfer Department at the University of Bordeaux
• MATTER (Materials e-Learning Resources) at the University of Liverpool
• CORE-Materials Open Educational Resources for Materials Science & Engineering
• Materials Research CEIT Research Institute
• Manufacturing engineering and mechanical properties of plastic parts – INTEMA (Research Institute), Universidad Nacional de Mar del Plata – CONICET

This article is about the philanthropist. For institutions named after him, see Johns Hopkins University and Johns Hopkins Hospital.

Johns Hopkins
Born	(1795-05-19)May 19, 1795 Anne Arundel County, Maryland, US
Died	December 24, 1873(1873-12-24) (aged 78) Baltimore, Maryland, US
Occupation	Entrepreneur, investor, philanthropist, abolitionist
Net worth	USD $10 million at the time of his death (approximately 1/944th of US GNP)[1]
Religion	Quaker

Johns Hopkins (May 19, 1795^[2] – December 24, 1873) was an American entrepreneur, abolitionist and philanthropist of 19th-century Baltimore, Maryland.

His bequests founded numerous institutions bearing his name, including Johns Hopkins Hospital, Johns Hopkins University, Johns Hopkins School of Nursing, Johns Hopkins School of Medicine, and Johns Hopkins Bloomberg School of Public Health.

A biography entitled Johns Hopkins: A Silhouette written by his cousin, Helen Hopkins Thom, was published in 1929 by the Johns Hopkins University Press.

Early life[link]

Johns Hopkins was born on May 19, 1795, to Samuel Hopkins (1759–1814) of Anne Arundel County, Maryland, and Hannah Janney (1774–1864), of Loudoun County, Virginia. Home was Whitehall, a 500-acre (two km²) tobacco plantation in Anne Arundel County.^[3] His first name derives from a maternal great-grandmother, Margaret Johns, who passed it on to her son.

The Hopkins family were members of the Society of Friends (Quakers). In 1807 they emancipated their slaves in accordance with their local Society decree, which called for freeing the able-bodied and caring for the others, who would remain at the plantation and provide labor as they could.^[4] The second eldest of eleven children, 12 year-old Johns was required to work on the farm, interrupting his formal education. From 1806 to 1809, he likely attended The Free School of Anne Arundel County, which was located in today's Davidsonville, Maryland.

In 1812, at the age of 17, Hopkins left the plantation to work in his uncle Gerard Hopkins' Baltimore wholesale grocery business. While living with his uncle's family, Johns and his cousin, Elizabeth, fell in love; however, the Quaker taboo against marriage of first cousins was especially strong, and neither Johns nor Elizabeth ever married.^[3]

As he became able, Hopkins provided for his extended family, both during his life and posthumously through his will. He bequeathed a home for Elizabeth, where she lived until her death in 1889.

Whitehall Plantation is located in today's Crofton, Maryland. Its home, since restored and modified, is on Johns Hopkins Road, adjacent to Reidel Road. The heavily landscaped property is surrounded by Walden Golf Course, and bears a historic marker.

Business years[link]

Hopkins' early experiences and successes in business came when he was put in charge of the store while his uncle was away during the War of 1812. After seven years with his uncle, Hopkins went into business together with Benjamin Moore, a fellow Quaker. The business partnership was later dissolved with Moore purporting Hopkins' penchant for capital accumulation as the cause for the divide.^[3]

After Moore's withdrawal, Hopkins partnered with three of his brothers and established Hopkins & Brothers. The company prospered by selling various wares in the Shenandoah Valley from Conestoga wagons, sometimes in exchange for corn whiskey, which was then sold in Baltimore as "Hopkins' Best". The bulk of Hopkins' fortune however was made by his judicious investments in a myriad of ventures, most notably the Baltimore and Ohio Railroad (B&O), of which he became a Director in 1847 and Chairman of the Finance Committee in 1855. He was also President of Merchants' Bank as well as director of a number of other organizations.^[5]

A charitable individual, Hopkins put up his own money more than once to not only aid Baltimore City during times of financial crises, but also to twice bail the railroad out of debt, in 1857 and 1873.^[6] In 1996, Johns Hopkins ranked 69th in "The Wealthy 100: From Benjamin Franklin to Bill Gates - A Ranking of the Richest Americans, Past and Present."^[7]

Civil War[link]

One of the first campaigns of the American Civil War was planned at Johns Hopkins' summer estate, Clifton, where he had also entertained a number of foreign dignitaries including the future King Edward VII.^[8] Hopkins was a strong supporter of the Union, unlike most Marylanders, who sympathized with and often supported the South and the Confederacy.^[9] During the Civil War, Clifton became a frequent meeting place for local Union sympathizers, and federal officials.

Hopkins' support of Abraham Lincoln also often put him at odds with some of Maryland's most prominent people, particularly Supreme Court Justice Roger B. Taney, who continually opposed Lincoln's presidential decisions, such as his policies of limiting habeas corpus and stationing troops in Maryland. In 1862 Hopkins wrote a letter to Lincoln requesting the President not to heed the detractors' calls and continue to keep soldiers stationed in Maryland. Hopkins also pledged financial and logistic support to Lincoln, in particular the free use of the B&O railway system.^[10][11]

Abolitionism[link]

Johns Hopkins is described as being an "abolitionist before the word was even invented", having been represented as such both prior to the Civil War period, as well as during the Civil War and Reconstruction Era.^[12][13][14] There are several accounts that describe the abolitionist influence Hopkins was privy to as a 12 year old participant in his parents' emancipation of their family's slaves in 1807.^[3] Prior to the Civil War Johns Hopkins worked closely with two of America's most famous abolitionists, Myrtilla Miner^[15] and Henry Ward Beecher.^[16] During the Civil War Johns Hopkins, being a staunch supporter of Lincoln and the Union, was instrumental in bringing fruition to Lincoln's emancipatory vision.^[17][18]

After the Civil War and during Reconstruction, Johns Hopkins' stance on abolitionism infuriated many prominent people in Baltimore.^[19][20] During the American Reconstruction period to his death ^[21] his abolitionism was expressed in the documents founding the Johns Hopkins Institutions, and reported in newspaper articles before, during, and after the founding of these institutions. Before the war, there was significant written opposition to his support for Myrtilla Miner's founding of a school for African American females^[22] (now the University of the District of Columbia). Similarly, opposition (and some support) was expressed during Reconstruction, such as in 1867, the same year he filed papers incorporating the Johns Hopkins Institutions, when he attempted unsuccessfully to stop the convening of the Constitutional Convention where the Democratic Party came into power and where a new Constitution, the Constitution still in effect, was voted to replace the Constitution of the Radical Republicans previously in power.^[23]

Apparent also in the literature of the times was opposition, and support for, the various other ways he expressed opposition to the racial practices that were beginning to emerge, and re-emerge as well, in the city of Baltimore, the state of Maryland, the nation and in the posthumously constructed and founded institutions that would carry his name,^[24] A Baltimore American journalist praised Hopkins for founding three institutions, a university, a hospital and an orphan asylum, specifically for colored children, adding that Hopkins was a "man (beyond his times) who knew no race" citing his provisions for both blacks and whites in the plans for his hospital. The reporter also pointed to similarities between Benjamin Franklin's and Johns Hopkins' views on hospital care and construction, such as their shared interest in free hospitals and the availability of emergency services without prejudice. This article, first published in 1870, also accompanied Hopkins' obituary in the Baltimore American as a tribute in 1873. Cited in many of the newspaper articles on him during his lifetime and immediately after his death were his provisions of scholarships for the poor, and quality health services for the underserved, the poor without regard to their age, sex and color, the colored children asylum and other orphanages, the mentally ill and convalescents.

Philanthropy[link]

Living his entire adult life in Baltimore, Hopkins made many friends among the city's social elite, many of them Quakers. One of these friends was George Peabody, who was also born in 1795, and who in 1857 founded the Peabody Institute in Baltimore. Other examples of public giving were evident in the city, as public buildings housing free libraries, schools and foundations sprang up along the city's widening streets. On the advice of Peabody, some believe, Hopkins determined to use his great wealth for the public good.

The Civil War had taken its toll on Baltimore, however, as did the yellow fever and cholera epidemics that repeatedly ravaged the nation's cities, killing 853 in Baltimore in the summer of 1832 alone. Hopkins was keenly aware of the city's need for medical facilities, particularly in light of the medical advances made during the war, and in 1870 he made a will setting aside seven million dollars - mostly in B&O stock - for the incorporation of a free hospital and affiliated medical and nurse's training colleges, as well as an orphanage for colored children and a university. Many board members were on both boards. The hospital and orphan asylum would each be overseen by the 12-member hospital board of trustees, and the university by the 12-member university board of trustees. Johns Hopkins' bequest was used to posthumously found the Johns Hopkins Colored Children Orphan Asylum ^[25] first as he requested, in 1875; the Johns Hopkins University in 1876; the Johns Hopkins Press, the longest continuously operating academic press in America, in 1878; the Johns Hopkins Hospital and the Johns Hopkins School of Nursing in 1889; the Johns Hopkins University School of Medicine 1893; and the Johns Hopkins School of Hygiene and Public Health in 1916.

Johns Hopkins' views on his bequests, and on the duties and responsibilities of the two board of trustees, especially the hospital board of trustees led by his friend and fellow Quaker Francis King, were formally stated primarily in four documents, the incorporation papers filed in 1867, his instruction letter to the hospital trustees dated March 12, 1873, his will, which was quoted from extensively in his Baltimore Sun obituary,^[26] and in his will's two codicils, one dated 1870 and the other dated 1873.^[27]

In these documents, Hopkins also made provisions for scholarships to be provided for poor youths in the states where Johns Hopkins had made his wealth, as well as assistance to orphanages other than the one for African American children, to members of his family, to those he employed, black and white, his cousin Elizabeth, and, again, to other institutions for the care and education of youths regardless of color and the care of the elderly, and the ill, including the mentally ill, and convalescents.

John Rudolph Niernsee, one of the most famous architects of the time, designed the orphan asylum and helped to design the Johns Hopkins Hospital. The original site for the Johns Hopkins University had been chosen personally by Hopkins. According to his will, it was to be located at his summer estate, Clifton. However, a decision was made not to found the university there. The property, now owned by the city of Baltimore, is the site of a golf course and a park named Clifton Park. While the Johns Hopkins Colored Children Orphan Asylum was founded by the hospital trustees, the other institutions that carry the name of "Johns Hopkins" were founded under the administration of the first president of the Johns Hopkins University and Johns Hopkins Hospital, Daniel Coit Gilman and his successors.

Colored Children Orphan Asylum[link]

As per Johns Hopkins' instruction letter, the Johns Hopkins Colored Children Orphan Asylum (JHCCOA)^[28] was founded first, in 1875, a year before Gilman's inauguration, now the founding date of the university. The construction of the asylum, including its educational and living facilities, was praised by The Nation and the Baltimore American, the latter stating that the orphan asylum was a place where "nothing was wanting that could benefit science and humanity". As was done for other Johns Hopkins Institutions, it was planned after visits and correspondence with similar institutions in Europe and America.

The Johns Hopkins Orphan Asylum opened with 24 boys and girls. Under Gilman and his successors, this orphanage was later changed to serve as an orphanage and training school for black female orphans principally as domestic workers, and next as an "orthopedic convalescent" home and school for "colored crippled" children and orphans. The asylum was eventually closed in 1924 nearly fifty years after it opened, and was never reopened.

Hospital, University, Press, and Schools of Nursing and Medicine[link]

As per Hopkins' March 1873 Instruction Letter, the School of Nursing was founded alongside the Hospital in 1889 by the hospital board of trustees in consultation with Florence Nightingale. Both the nursing school and the hospital were founded over a decade after the founding of the orphan asylum in 1875 and the university in 1876. Hopkins' instruction letter explicitly stated his vision for the hospital; first, to provide assistance to the poor of "all races", no matter the indigent patient's "age, sex or color"; second, that wealthier patients would pay for services and thereby subsidize the care provided to the indigent; third, that the hospital would be the administrative unit for the orphan asylum for African American children which was to receive $25,000 in annual support out of the hospital's half of the endowment; and fourth, that the hospital and orphan asylum should serve 400 patients and 400 children respectively, fifth, that the hospital should be part of the university, and, sixth, that religion but not sectarianism should be an influence in the hospital.

By the end of Gilman's presidency, Johns Hopkins University, Johns Hopkins Press, Johns Hopkins Hospital and Johns Hopkins School of Nursing, and Johns Hopkins School of Medicine, and Johns Hopkins Colored Children Orphan Asylum had been founded, the latter by the trustees, and the others in the order listed under the Gilman administration. "Sex" and "color" were major issues in the early history of the Johns Hopkins Institutions. The founding of the School of Nursing is usually linked to Johns Hopkins' statements in his March 1873 instruction letter to the trustees that "I desire you to establish, in connection with the hospital, a training school for female nurses. This provision will secure the services of women competent to care for those sick in the hospital wards, and will enable you to benefit the whole community by supplying it with a class of trained and experienced nurses".

Women's most well known success after the founding of the nursing school was their requirement that they be allowed to attend Johns Hopkins medical institutions after they provided funds that made possible the opening of the School of Medicine in 1893. Five African American women were among the first women enrolled in the Johns Hopkins University's undergraduate school in 1970. Furthermore Kelly Miller and Frederick Scott were the first persons of African descent to attend the Johns Hopkins University's graduate and undergraduate schools, respectively. Frederick Scott was the first graduate of African descent from Johns Hopkins University, and he, Robert Gamble, and Kenyan-born James Nabwangu were the first graduates of African descent from Johns Hopkins University's undergraduate school, and Johns Hopkins' medical schools respectively. Those employees holding jobs in the service sector are those of African descent who have the longest and most continuous history at the Johns Hopkins Institutions.

Legacy[link]

Johns Hopkins Monument

(at Johns Hopkins University)

Following Hopkins' death, the Baltimore Sun wrote a lengthy obituary which closed thus: "In the death of Johns Hopkins a career has been closed which affords a rare example of successful energy in individual accumulations, and of practical beneficence in devoting the gains thus acquired to the public." His contribution to the university that has become his greatest legacy was, by all accounts, the largest philanthropic bequest ever made to an American educational institution.

Johns Hopkins' Quaker faith and his early life experiences, in particular the 1807 emancipation, had a lasting influence throughout his life and his posthumous legacy as a businessman, railroad man, banker, investor, ship owner,^[29] philanthropist and a founder of several Institutions. From very early on, Johns Hopkins had looked upon his wealth as a trust to benefit future generations. He is said to have told his gardener that, "like the man in the parable, I have had many talents given to me and I feel they are in trust. I shall not bury them but give them to the lads who long for a wider education"; his philosophy quietly anticipated Andrew Carnegie's much publicized Gospel of Wealth by more than 25 years.^[30]

His philanthropy, banking and other business practices were founded neither on slavery nor on the separate but unequal racism of the post Civil War years of his life. In this vein, integral parts of his legacy, as an emancipator, a founder of an orphan asylum for African-American youths, a staunch advocate of abolitionism and of quality care not just for those physically ill, but also for the elderly, the poor, no matter their age, gender, or skin color, and the mentally ill, have by and large been overlooked, even in the institutions that carry his name.

In 1973 Johns Hopkins was cited prominently in the Pulitzer Prize winning book The Americans: The Democratic Experience by Daniel Boorstin, former head of the Library of Congress. From November 14, 1975 to September 6, 1976 Hopkins portrait was displayed at the National Portrait Gallery in an exhibit on the democratization of America based on Boorstin's book. In 1989, the United States Postal Service issued a $1 postage stamp in Johns Hopkins' honor, as part of the Great Americans series.^[31]

References[link]

External links[link]

	United States portal
	Maryland portal

• Genealogical Records on Marylanders
• Thom and Jacob discuss his love for his cousin and Quaker traditions
• In his 1887 memoir, Baltimore and the Nineteenth of April, 1861: A Study of the War, George William Brown cites Johns Hopkins as a wealthy Union man in Baltimore, a city with strong Confederate and Southern leanings
• In The Chronicles of Baltimore: Being a Complete History of "Baltimore Town" and Baltimore City from the Earliest Period to the Present Time published in 1874, John Thomas Scharf cited the 1873 instruction letter to the hospital trustees and a city council resolution thanking Johns Hopkins for his philanthropy. Thom's biography and New York and Maryland newspapers were sources that published parts or all of this letter
• The Institutional Records of The Johns Hopkins Hospital Colored Orphan Asylum
• Abstract Johns Hopkins Dream for a Model of its Kind: The JHH Colored Orphans Asylum", 2000 Conference International Society for the History of Medicine BY Dr. P. Reynolds
• Grave site of Johns Hopkins
• Graveside ceremony for Johns Hopkins
• Baltimore and the Nineteenth of April, 1861: A Study of the War, the memoir of George William Brown then the mayor of Baltimore city, later a member of the university board of trustees of the Johns Hopkins University
• The Chronicles of Baltimore: Being a Complete History of "Baltimore Town" and Baltimore City from the Earliest Period to the Present Time published in 1874 by John Thomas Scharf
• "If He Could See Us Now: Mr. Johns Hopkins' Legacy Strong University, Hospital Benefactor Turned 200 on May 19, 1995", Mike Field, the author, contradicts this statement
• Chronology, Nursing school
• The Institutional Records of The Johns Hopkins Hospital Colored Orphan
• Abstract Johns Hopkins Dream for a Model of its Kind: The JHH Colored Orphans Asylum" By Dr. P. Reynolds
• "If He Could See Us Now: Mr. Johns Hopkins' Legacy Strong University, Hospital Benefactor Turned 200 on May 19, 1995" by Mike Field a writer for the Johns Hopkins Gazette. Field, Thom, and Jacob called Johns Hopkins an abolitionist. See also The Racial Record of Johns Hopkins University in the Journal of Blacks in Higher Education, No. 25, Autumn, 1999, pp. 42-43/ JSTOR
• Johns Hopkins, Maryland State Archives
• "The History of African Americans @ Johns Hopkins University" See in particular the chronology and the paper by Danton Rodriguez.