Materials Engineering Glossary
25 essential terms — because precise language is the foundation of clear thinking in Materials Engineering.
Showing 25 of 25 terms
A metallic substance composed of two or more elements, where at least one is a metal, combined to achieve properties not available in pure elements.
A heat treatment involving heating a material above a critical temperature, holding, and then slowly cooling to relieve internal stresses, increase ductility, and refine grain structure.
The face-centered cubic (FCC) phase of iron stable at high temperatures (above 912 degrees Celsius for pure iron). It is the starting phase for most steel heat treatments.
Sudden, catastrophic failure with little or no plastic deformation. Characterized by flat fracture surfaces and rapid crack propagation.
An inorganic, non-metallic solid material prepared by heating and cooling. Typically hard, brittle, and resistant to heat and chemical attack.
An engineered material made from two or more constituents with different properties that remain distinct within the finished structure.
The gradual destruction of materials, usually metals, by electrochemical or chemical reaction with their environment.
Time-dependent permanent deformation of a material under sustained stress at elevated temperature.
The three-dimensional periodic arrangement of atoms or molecules in a crystalline solid, defined by a unit cell that repeats in space.
A linear crystallographic defect around which atoms are misaligned. Dislocations are the primary mechanism by which metals deform plastically.
A material's ability to undergo significant plastic deformation before fracture, typically measured as percent elongation or percent reduction in area.
A polymer with viscoelastic properties, capable of recovering its original shape after large deformations. Natural and synthetic rubbers are common elastomers.
Weakening and eventual failure of a material caused by repeatedly applied cyclic loads, often at stress levels below the material's static yield strength.
The body-centered cubic (BCC) phase of iron stable at room temperature. It is relatively soft, ductile, and magnetic.
A quantitative measure of a material's resistance to crack propagation, expressed as the critical stress intensity factor $K_{IC}$.
An individual crystallite within a polycrystalline material. Each grain has a uniform crystal orientation that differs from its neighbors.
A material's resistance to localized plastic deformation, typically measured by indentation tests such as Brinell, Rockwell, or Vickers.
A very hard, supersaturated solid solution of carbon in a body-centered tetragonal iron lattice, formed by rapid quenching of austenite.
The structure of a material as revealed by microscopy, including grain size, phase distribution, inclusions, and defects, typically at magnifications of 25x to 1000x.
A large molecule composed of many repeating subunits (monomers) bonded together. Polymers can be thermoplastic, thermosetting, or elastomeric.
Rapid cooling of a heated material (typically in water, oil, or air) to lock in a high-temperature microstructure, often producing martensite in steels.
A material with electrical conductivity between that of a conductor and an insulator, whose properties can be modified by doping with impurity atoms.
A process of compacting and forming a solid mass of material by heat and/or pressure without melting to the point of liquefaction, commonly used for ceramics and powder metals.
The maximum stress a material can withstand while being stretched or pulled before breaking, also known as ultimate tensile strength (UTS).
A polymer that becomes pliable or moldable above a specific temperature and solidifies upon cooling. It can be repeatedly reheated and reshaped.