Materials science
From ePedia, the electronic encyclopedia
Materials science is the multidisciplinary field relating the performance and function of matter in any and all applications to its micro, nano, and atomic-structure, and vice versa. It is closely related to applied physics, chemical engineering and chemistry, bioengineering and biology, mechanical engineering, civil engineering and electrical engineering; it is indeed one of the most multidisciplinary science and engineering fields. Fundamentally, all of nanoscience and nanotechnology is materials science. Because of this, in recent years materials science has been propelled to the forefront at many universities, sometimes controversially: many academics feel that the 'nano' buzzword is bringing in large amounts of funding at the cost of detracting from the teaching of fundamental materials science by putting too much emphasis on devices and applications which may or may not see fruition as working products.
History is often defined by the materials used by advanced civilizations of an era; the stone age, bronze age, and steel age are examples. Materials science in a primitive form is thus one of the oldest forms of engineering and applied science. Modern materials science indeed evolved directly from metallurgy, which itself evolved from mining. A true understanding of materials, however, was not possible until the realization by Willard Gibbs in the second half of the 19th century of the thermodynamic properties which relate how atoms are arranged in various phases (whether they are various types of solids, liquids, or gases) to the properties of the material. Since then, materials science has been the area of research where rather than looking for and discovering materials and exploiting their properties, one instead aims to understand materials fundamentally so that we can invent and create new materials with the properties we desire. Modern materials science is a product of the space race: the understanding and engineering of the metallic alloys (metallurgy) and other materials that went into the construction of space vehicles was one of the enablers of space exploration. Until the 1960's (and in some cases until decades afterwards), many university departments which are now materials science departments were metallurgy departments. Since then the field has broadened to include every class of materials including metallurgy, ceramics, polymers, electronic materials such as semiconductors and magnetic materials, and biological materials such as medical implants. Besides space exploration, materials science has enabled revolutionary technologies such as plastics, semiconductors, and biomaterials.
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, the way in which the material was processed (formed or created) being one determinant of the structure and thus properties. Say we want to create a high-performance metal that is harder, stronger, and tougher than any other metal we have. We will first test and measure (characterize) a variety of existing metals to compare their properties and understand their structure. Structurally we would like to know how atoms pack on the finest scale to how clumps of atoms and impurities organize themselves, as well as the defects that are present. We will relate the structure to how the material was processed, and draw conclusions as to what processing conditions we may use to create the desired properties in our new high-performance metal. After creating it, we will characterize it and see what happened, hopefully learning what went wrong and what went right. Although such a case is broadly oversimplified and straightforward, the collective field of materials science is in effect carrying this process out for a multitude of material types, properties, and applications.
An old adage in materials science says: "materials are like people; it is the defects that make them interesting." Indeed, a perfect crystal of a material like aluminium is technologically impossible (it may be interesting to note that it would be roughly 10,000 times stronger than any aluminum available today); rather, introduce the right defects into the aluminium such as precipitates, grain boundaries (Hall Petch relationship), interstitial atoms, or substitutional atoms (solid solution strengthening) in the correct quantity, and you will have a high strength alloy that is used in the manufacture of most bicycles, automobiles, and airplanes. Similarly, it is the impurities which give minerals and glass their color; it is the imperfections (as dislocations) in the crystal structure of steel which gives it its strength; and it is the impurities we introduce into silicon which give us the ability to use it to form microchips.
The widespread applications of materials science give rise to the title materials science and engineering. 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/or to troubleshoot. 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, etc.).
The overlap between physics and materials science has led to "materials physics," which is a field of physics concerned with the physical properties of materials. The approach is generally more macroscopic and applied than in condensed matter physics. See the important publications in materials physics for more details on this field of study.
History is often defined by the materials used by advanced civilizations of an era; the stone age, bronze age, and steel age are examples. Materials science in a primitive form is thus one of the oldest forms of engineering and applied science. Modern materials science indeed evolved directly from metallurgy, which itself evolved from mining. A true understanding of materials, however, was not possible until the realization by Willard Gibbs in the second half of the 19th century of the thermodynamic properties which relate how atoms are arranged in various phases (whether they are various types of solids, liquids, or gases) to the properties of the material. Since then, materials science has been the area of research where rather than looking for and discovering materials and exploiting their properties, one instead aims to understand materials fundamentally so that we can invent and create new materials with the properties we desire. Modern materials science is a product of the space race: the understanding and engineering of the metallic alloys (metallurgy) and other materials that went into the construction of space vehicles was one of the enablers of space exploration. Until the 1960's (and in some cases until decades afterwards), many university departments which are now materials science departments were metallurgy departments. Since then the field has broadened to include every class of materials including metallurgy, ceramics, polymers, electronic materials such as semiconductors and magnetic materials, and biological materials such as medical implants. Besides space exploration, materials science has enabled revolutionary technologies such as plastics, semiconductors, and biomaterials.
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, the way in which the material was processed (formed or created) being one determinant of the structure and thus properties. Say we want to create a high-performance metal that is harder, stronger, and tougher than any other metal we have. We will first test and measure (characterize) a variety of existing metals to compare their properties and understand their structure. Structurally we would like to know how atoms pack on the finest scale to how clumps of atoms and impurities organize themselves, as well as the defects that are present. We will relate the structure to how the material was processed, and draw conclusions as to what processing conditions we may use to create the desired properties in our new high-performance metal. After creating it, we will characterize it and see what happened, hopefully learning what went wrong and what went right. Although such a case is broadly oversimplified and straightforward, the collective field of materials science is in effect carrying this process out for a multitude of material types, properties, and applications.
An old adage in materials science says: "materials are like people; it is the defects that make them interesting." Indeed, a perfect crystal of a material like aluminium is technologically impossible (it may be interesting to note that it would be roughly 10,000 times stronger than any aluminum available today); rather, introduce the right defects into the aluminium such as precipitates, grain boundaries (Hall Petch relationship), interstitial atoms, or substitutional atoms (solid solution strengthening) in the correct quantity, and you will have a high strength alloy that is used in the manufacture of most bicycles, automobiles, and airplanes. Similarly, it is the impurities which give minerals and glass their color; it is the imperfections (as dislocations) in the crystal structure of steel which gives it its strength; and it is the impurities we introduce into silicon which give us the ability to use it to form microchips.
The widespread applications of materials science give rise to the title materials science and engineering. 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/or to troubleshoot. 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, etc.).
The overlap between physics and materials science has led to "materials physics," which is a field of physics concerned with the physical properties of materials. The approach is generally more macroscopic and applied than in condensed matter physics. See the important publications in materials physics for more details on this field of study.
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