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| A scientific discipline that is primarily concerned with the search for basic knowledge about the internal structure, properties, and processing of materials |
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| engineering discipline primarily concerned with the use of fundamental and applied knowledge of materials |
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| inorganic materials that are characterized by high thermal and electrical conductivities |
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| materials consisting of compounds of metals and nonmetals. usually hard and brittle. i.e. clay, glass, etc |
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| materials consisting of long molecular chains or networks of low-weight elements. low electrical conductivities |
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| materials that are mixtures of two or more materials |
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| materials used in electronics. silicon and gallium arsenide |
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| the energy required to remove an electron from its ground state in an atom to infinity |
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| set of four numbers necessary to characterize each electron in an atom. |
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| distribution of all the electrons in an atom according to their atomic orbitals |
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| primary bond resulting from the electrostatic attraction of oppositely charged ions |
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| primary bond resulting from the sharing of electrons. often involves overlapping of half-filled orbitals |
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| solid composed of atoms, ions, molecules arranged in a pattern that is repeated in space |
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| volume of atoms in a selected unit cell divided by the volume of the unit cell |
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| atomic packing factor (APF) |
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| the ability of a metal to exist in two or more crystal structures |
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| the formation of very small regions of a new solid phase in a pure metal that can grow until solidification is complete |
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| the formation of very small nuclei of a new solid phase at the interfaces of solid impurities that lower the critical size at a particular temperature of stable solid nuclei |
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| a single crystal in a polycrystalline aggregate |
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| a crystalline structure that contains many grains |
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| polycrystalline structure |
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| a mixture of two or more metals and a nonmetal |
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| an alloy of two or more metals or a metal and a nonmetal that is a single-phase atomic mixture. can be substitutional or interstitial |
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| a point imperfection in an ionic crystal in which a cation vacancy is associated with an interstitial cation |
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| a point imperfection in an ionic crystal in which a cation vacancy is associated with an anion vacancy |
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| crystalline imperfection in which a lattice distortion is centered around a line and THE SLIP VECTOR IS PERPENDICULAR TO THE DISLOCATION LINE |
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| crystalline imperfection in which a lattice distortion is centered around a line and THE SLIP VECTOR IS PARALLEL TO THE DISLOCATION LINE |
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| surface imperfection that separates crystals of different orientations in a polycrystalline aggregate |
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| a mirror image misorientation of the crystal structure that is considered a surface defect |
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| a heat treatment given to a metal to soften it |
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| permanent deformation of metals and alloys above/below the temperature at which a strain-free micro structure is produced continuously. which causes strain hardening?? |
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| cold/hard working...cold causes strain-hardening |
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| the stress at which a specific amount of strain occurs in the engineering tensile test |
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| the maximum stress in the engineering stress-strain diagram |
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| a measure of the resistance of a material to permanent deformation |
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| the process of atoms moving over each other during the permanent deformation of a metal |
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| a plastic deformation process that occurs in some metals and under certain conditions. in this process a large group of atoms are displaced together to form a region of a metal crystal lattice that is a mirror image of a similar region along a twinning plane |
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| the first stage in the annealing process that results in removal of residual stresses and formation of low energy dislocation configurations |
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| the second stage of the annealing process in which new grains start to grow and dislocation density decreases significantly |
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| the third stage of annealing process in which new grains start to grow in an equiaxed manner |
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| mode of fracture characterized by slow crack propagation. surfaces of metals are usually dull with a fibrous appearance |
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| phenomenon leading to fracture under repeated stresses having a maximum value less than the ultimate strength of the material |
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| time-dependent deformation of a material when subjected to a constant load or stress |
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| a physically homogeneous and distinct portion of a material system |
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| plots of temp vs. time acquired during solidification of a metal. provides phase change information |
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| a system in which there is only one solid phase...there is only one solid-state structure |
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| a phase transformation in which all the liquid phase transforms on cooling into two solid phases isothermally |
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| a composition that is to the left of the eutectic point |
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| a composition that is to the right of the eutectic point |
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| hypereutectic composition |
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| an interstitial solid solution of carbon in FCC iron. the maximum solid solubility of carbon in this material is 2% |
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| an interstitial solid solution of carbon in BCC iron; maximum solid solubility of carbon is .02% |
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| an intermetallic compound of Fe_3_C; hard and brittle substance |
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| a mixture of alpha ferrite and cementite phases in parallel plates produced by the eutectoid decomposition of austenite |
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| a supersaturated interstitial solid solution of carbon in body-centered tetragonal iron |
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| the process of reheating a quenched steel to increase its toughness and ductility |
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| plastic material that requires heat to make it formable and retains its shape upon cooling. can be repeatedly softened when heated and harden when cooled |
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| a plastic material that has undergone a chemical reaction by the action of heat, catalysis, etc...cannot be remelted since when they are heated they degrade and decompose |
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| chemical reaction in which high-molecular-mass molecules are formed from monomers |
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| number of equidistant nearest neighbors to an atom or ion in a unit cell of a crystal structure |
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| a materials system composed of a mixture or combination of two or more micro or macro constituents that differ in form and chemical composition and are insoluble in each other |
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| tensile strength of a material divided by its density |
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| specific tensile strength |
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| natural composite material consisting mainly of a complex array of cellulose fibers in a polymeric material matrix made up primarily of lignin |
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| deterioration of a material resulting from chemical attack by its environment |
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| measure of the difficulty of electric current's passage through a unit volume of material |
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| the unfilled energy levels into which electrons can be excited to become conductive electrons |
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| semiconducting material that is essentially pure and for which the energy gap is small enough to be surmounted by thermal excitation |
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| semiconducting material that has been doped with another element. in the first type impurities donate electrons with conduction band energies, in the second type impurities provide electron holes |
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| the first is n-type semiconductor and the second is p-type |
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| an abrupt junction or boundary between p and n type regions within a single crystal of a semiconducting material |
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| electric device consisting of conducting plates or fould separated by layers of dielectric material and capable of storing electic charge |
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| a magnetic material with a high permeability and a low coercive force |
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| magnetic material with a high coercive force and a high saturation induction |
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| a point in an array in which all the points have identical surroundings |
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| a graphical representation of the phases present at various temperatures, pressures and compositions |
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| the ability of a material to withstand cracks |
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