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The Materials Science Tetrahedron
The Materials Science Tetrahedron

Materials science or materials engineering is an interdisciplinary field involving the properties of matter and its applications to various areas of science and engineering. Science (from the Latin scientia, meaning " Knowledge " or "knowing" is the effort to discover, and increase human understanding Engineering is the Discipline and Profession of applying technical and scientific Knowledge and This science investigates the relationship between the structure of materials at atomic or molecular scale and their macroscopic properties. It includes elements of applied physics and chemistry, as well as chemical, mechanical, civil and electrical engineering. Chemistry (from Egyptian kēme (chem meaning "earth") is the Science concerned with the composition structure and properties Chemical engineering is the branch of Engineering that deals with the application of Physical science (e Mechanical Engineering is an Engineering discipline that involves the application of principles of physics for analysis Design, Manufacturing Civil engineering is a professional engineering discipline that deals with the design construction and maintenance of the physical and naturally built Electrical engineering, sometimes referred to as electrical and electronic engineering, is a field of Engineering that deals with the study and application of With significant media attention to nanoscience and nanotechnology in recent years, materials science has been propelled to the forefront at many universities. Nanotechnology, sometimes shortened to nanotech, refers to a field of Applied science whose theme is the control of matter on an Atomic and Molecular Nanotechnology, sometimes shortened to nanotech, refers to a field of Applied science whose theme is the control of matter on an Atomic and Molecular It is also an important part of forensic engineering and forensic materials engineering, the study of failed products and components. Forensic Engineering is the investigation of materials, products, Structures or components that fail or do not operate/function as A branch of Forensic engineering, the subject focuses on the material evidence from crime or accident scenes seeking defects in those materials which might explain why an accident occurred

Contents

History

The material of choice of a given era is often its defining point; the Stone Age, Bronze Age, and Steel Age are examples of this. The Stone Age is a broad prehistoric time period during which Humans widely used stone for toolmaking The term Bronze Age refers to a period in human cultural development when the most advanced Metalworking (at least in systematic and widespread use included techniques for The Industrial Revolution was a period in the late 18th and early 19th centuries when major changes in agriculture manufacturing and transportation had a profound effect on the Materials science is one of the oldest forms of engineering and applied science, deriving from the manufacture of ceramics. The word ceramic is derived from the Greek word κεραμικός ( keramikos) Modern materials science evolved directly from metallurgy, which itself evolved from mining. Metallurgy is a domain of Materials science that studies the physical and chemical behavior of metallic elements, their intermetallic compounds, and their A major breakthrough in the understanding of materials occurred in the late 19th century, when Willard Gibbs demonstrated that thermodynamic properties relating to atomic structure in various phases are related to the physical properties of a material. The 19th century of the Common Era began on January 1, 1801 and ended on December 31, 1900, according to the Gregorian calendar Josiah Willard Gibbs ( February 11, 1839 &ndash April 28, 1903) was an American theoretical Physicist, Chemist In Physics, thermodynamics (from the Greek θερμη therme meaning " Heat " and δυναμις dynamis meaning " History See also Atomic theory, Atomism The concept that matter is composed of discrete units and cannot be divided into arbitrarily tiny In the Physical sciences a phase is a Set of states of a macroscopic physical system that have relatively uniform chemical composition and physical properties 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. The Space Race was a competition of space exploration between the Soviet Union and the United States, which lasted roughly from 1957 to 1975 An alloy is a Solid solution or Homogeneous mixture of two or more elements, at least one of which is a Metal, which itself has The Chemical compound silicon dioxide, also known as silica or silox (from the Latin " Silex " is an Oxide Carbon (kɑɹbən is a Chemical element with the symbol C and its Atomic number is 6 Materials science has driven, and been driven by, the development of revolutionary technologies such as plastics, semiconductors, and biomaterials. Plastic is the general common term for a wide range of synthetic or semisynthetic organic solid materials suitable for the manufacture of industrial products A semiconductor' is a Solid material that has Electrical conductivity in between a conductor and an insulator; it can vary over that The development of biomaterials is not a new area of Science, having existed for around half a century

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. A polymer is a large Molecule ( Macromolecule) composed of repeating Structural units typically connected by Covalent Chemical bonds

Fundamentals of materials science

In materials science, rather than haphazardly looking for and discovering materials and exploiting their properties, one instead aims to understand materials fundamentally so that new materials with the desired properties can be created.

The basis of all 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. A physical property is any aspect of an object or substance that can be measured or perceived without changing its identity. 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, taken together and related through the laws of thermodynamics, govern a material’s microstructure, and thus its properties. In Physics, thermodynamics (from the Greek θερμη therme meaning " Heat " and δυναμις dynamis meaning " Microstructure refers to the microscopic description of the individual constituents of a Material.

An old adage in materials science says: "materials are like people; it is the defects that make them interesting". The manufacture of a perfect crystal of a material is currently physically impossible. In Materials science, a crystal is a Solid in which the constituent Atoms Molecules or Ions are packed in a regularly ordered repeating 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. Crystalline solids have a very regular atomic structure that is the local positions of atoms with respect to each other are repeated at the atomic scale Precipitation is the formation of a Solid in a Solution during a Chemical reaction. Grain boundary strengthening (or Hall-Petch strengthening) is a method of strengthening materials by changing their average Crystallite (grain size

Not all materials have a regular crystal structure. Polymers display varying degrees of crystallinity, and many are completely non-crystalline. A polymer is a large Molecule ( Macromolecule) composed of repeating Structural units typically connected by Covalent Chemical bonds Glasses, some ceramics, and many natural materials are amorphous, not possessing any long-range order in their atomic arrangements. Glass in the common sense refers to a Hard, Brittle, transparent Solid, such as that used for Windows many An amorphous solid is a Solid in which there is no Long-range order of the positions of the Atoms (Solids in which there is long-range atomic order are 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.

Materials in industry

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. BC 29000–25000 BC - First Ceramic appears 3rd millennium BC - Copper Metallurgy is invented and copper 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. Casting is a manufacturing process by which a liquid material is (usually poured into a mold which Rolling is a combination of Rotation (of a radially symmetric object and translation of that object with respect to a surface (either one or the other moves such that Welding is a fabrication process that joins materials usually Metals or Thermoplastics by causing coalescence. Ion implantation is a Materials engineering process by which ions of a material can be implanted into another solid thereby changing the physical properties of the Crystal growth is a major stage of a crystallization process, after the Nucleation stage Thin-film deposition is any technique for depositing a Thin film of material onto a substrate or onto previously deposited layers Sintering is a method for making objects from powder, by heating the material (below its Melting point - solid state sintering until its particles adhere Glassblowing is a glassforming technique that involves inflating the molten glass into a bubble or parison with the aid of the blowpipe or blow tube ), and analytical techniques (characterization techniques such as electron microscopy, x-ray diffraction, calorimetry, nuclear microscopy (HEFIB), Rutherford backscattering, neutron diffraction, etc. An electron microscope is a type of Microscope that uses Electrons to illuminate a specimen and create an enlarged image X-ray scattering techniques are a family of non-destructive analytical techniques which reveal information about the crystallographic structure chemical composition Calorimetry is the Science of measuring the Heat of Chemical Nuclear microscopy uses a device called a Microprobe. A microprobe is a device that uses electromagnetic or electrostatic lenses to focus an ion beam Rutherford backscattering spectrometry (RBS is an analytical technique used in Materials science. Neutron diffraction is a crystallographic method for the determination of the atomic and/or magnetic structure of a material ).

Besides material characterisation, 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 1/10th 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. Materials are physical Substances used as inputs to production or Manufacturing. The approach is generally more macroscopic and applied than in condensed matter physics. Condensed matter physics is the field of Physics that deals with the macroscopic physical properties of Matter. See important publications in materials physics for more details on this field of study. Optics Book of Optics

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. Steel is an Alloy consisting mostly of Iron, with a Carbon content between 0 In Metallurgy, stainless steel is defined as a Steel Alloy with a minimum of 11 Cast iron usually refers to grey cast iron, but identifies a large group of Ferrous Alloys which solidify with a Eutectic. Tool steel refers to a variety of Carbon and Alloy Steels that are particularly well-suited to be made into Tools Their suitability comes from Steel is an Alloy consisting mostly of Iron, with a Carbon content between 0 Iron alloyed with various proportions of carbon gives low, mid and high carbon steels. Carbon steel, also called plain carbon steel, is Steel where the main alloying constituent is Carbon. For the steels, the hardness and tensile strength of the steel is directly related to the amount of carbon present, with increasing carbon levels also leading to lower ductility and toughness. The addition of silicon and graphitization will produce cast irons (although some cast irons are made precisely with no graphitization). The addition of chromium, nickel and molybdenum to carbon steels (more than 10%) gives us stainless steels.

Other significant metallic alloys are those of aluminium, titanium, copper and magnesium. WikipediaNaming Titanium (taɪˈteɪniəm is a Chemical element with the symbol Ti and Atomic number 22 Copper (ˈkɒpɚ is a Chemical element with the symbol Cu (cuprum and Atomic number 29 Magnesium (mægˈniːziəm is a Chemical element with the symbol Mg, Atomic number 12 Atomic weight 24 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. Copper alloys are Alloys with Copper as their principal component The term Bronze Age refers to a period in human cultural development when the most advanced Metalworking (at least in systematic and widespread use included techniques for 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.

Other than metals, polymers and ceramics 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. Polyethylene or polythene ( IUPAC name poly(ethene) is a Thermoplastic commodity heavily used in consumer products (notably the Polypropylene or polypropene ( PP) is a Thermoplastic Polymer, made by the Chemical industry and used in a wide variety of applications Polystyrene ˌpɒliˈstaɪriːn ( IUPAC Polyphenylethene is an aromatic Polymer made from the aromatic Monomer Styrene Overview Nylon is a Thermoplastic silky material first used commercially in a nylon- Bristled Toothbrush (1938 followed more famously by Polyester is a category of Polymers which contain the Ester Functional group in their main chain A polyurethane, commonly abbreviated PU, is any Polymer consisting of a chain of organic units joined by urethane links 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. An insulator, also called a Dielectric, is a material that resists the flow of Electric current. Packaging is the science art and technology of enclosing or protecting products for distribution storage sale and use Food storage is both a traditional domestic skill and is important industrially 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. Plasticizers are additives that increase the Plasticity or Fluidity of the material to which they are added these include plastics cement concrete wallboard and 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.

It should be noted here that the dividing line 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. Polyethylene or polythene ( IUPAC name poly(ethene) is a Thermoplastic commodity heavily used in consumer products (notably the Ultra high molecular weight polyethylene ( UHMWPE) also known as high-modulus polyethylene ( HMPE) or high-performance polyethylene ( HPPE

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. An example would be steel-reinforced concrete; another 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 fibres or carbon fibres have been added for added strength, bulk, or electro-static dispersion. Composite materials (or composites for short are engineered Materials made from two or more constituent materials with significantly different physical or chemical Calcium carbonate is a Chemical compound with the Chemical formula Ca[[Carbon C]] O 3 Talc (derived from the Persian via Arabic talq) is a Mineral composed of Hydrated Magnesium Silicate with Fiberglass (also called fibreglass and glass fibre see Spelling differences) is material made from extremely fine Fibers of Glass. These additions may be referred to as reinforcing fibres, or dispersants, depending on their purpose.

Classes of materials (by bond types)

Materials science encompasses various classes of materials, each of which may constitute a separate field. Materials are sometimes classified by the type of bonding present between the atoms:

  1. Ionic crystals
  2. Covalent crystals
  3. Metals
  4. Intermetallics
  5. Semiconductors
  6. Polymers
  7. Composite materials
  8. Vitreous materials

Sub-fields of materials science

Some practitioners often consider rheology a sub-field of materials science, because it can cover any material that flows. Ceramography is the art and science of preparation examination and evaluation of Ceramic Microstructures Ceramography can be thought of as the Metallography Microstructure refers to the microscopic description of the individual constituents of a Material. A refractory is a material that retains its strength at high Temperatures ASTM C71 defines refractories as "non-metallic materials having those chemical and physical Reinforced Carbon-Carbon ( carbon-carbon or RCC) is a Composite material consisting of Carbon fiber reinforcement in a matrix of Graphite Silicon carbide ( is a compound of Silicon and Carbon bonded together to form Ceramics but it also occurs in nature as the extremely rare mineral The word ceramic is derived from the Greek word κεραμικός ( keramikos) Rheology is the study of the flow of matter mainly liquids but also soft solids or solids under conditions in which they flow rather than deform elastically However, modern rheology typically deals with non-Newtonian fluid dynamics, so it is often considered a sub-field of continuum mechanics. Fluid dynamics is the sub-discipline of Fluid mechanics dealing with fluid flow: Fluids ( Liquids and Gases in motion Continuum mechanics is a branch of Mechanics that deals with the analysis of the Kinematics and mechanical behavior of materials modeled as a continuum e See also granular material. A granular material is a conglomeration of discrete Solid, macroscopic particles characterized by a loss of energy whenever the particles interact (the most common example would

Topics that form the basis of materials science

Important Journals

See also

Bibliography

References


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