(See related pages)
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| Hot working of metals | permanent deformation of metals and alloys above the temperature
at which a strain-free microstructure is produced continuously (recrystallization
temperature). (See page(s) 229, Sec. 5.1) |
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| Cold working of metals | permanent deformation of metals and alloys below the temperature
at which a strain-free microstructure is produced continuously (recrystallization
temperature). Cold working causes a metal to be strain-hardened. (See page(s) 229, Sec. 5.1) |
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| Percent cold reduction |  (See page(s) 229, Sec. 5.1) |
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| Annealing | a heat treatment given to a metal to soften it. (See page(s) 229, Sec. 5.1) |
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| Extrusion | a plastic forming process in which a material under high pressure is reduced
in cross section by forcing it through an opening in a die. (See page(s) 229, Sec. 5.1) |
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| Forging | a primary processing method for working metals into useful shapes in which
the metal is hammered or pressed into shape. (See page(s) 229, Sec. 5.1) |
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| Wire drawing | a process in which wire stock drawn through one or more tapered dies to
the desired cross section. (See page(s) 229, Sec. 5.1) |
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| Elastic deformation | if a metal deformed by a force returns to its original dimensions
after the force is removed, the metal is said to be elastically deformed. (See page(s) 230, Sec. 5.2) |
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| Engineering stress σ | average uniaxial force divided by original cross-sectional area
( σ = F / A0 ). (See page(s) 230, Sec. 5.2) |
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| Engineering strain ε | change in length of sample divided by the original length of sample
( ε = Δl / l0 ). (See page(s) 230, Sec. 5.2) |
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| Shear stress τ | shear force S divided by the area A over which the shear force acts ( τ = S / A). (See page(s) 230, Sec. 5.2) |
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| Shear strain γ | shear displacement a divided by the distance h over which the shear acts
( γ = a / h). (See page(s) 230, Sec. 5.2) |
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| Engineering stress-strain diagram | experimental plot of engineering stress versus
engineering strain; σ is normally plotted as the y axis and ε as the x axis. (See page(s) 230, Sec. 5.3) |
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| Modulus of elasticity E | stress divided by strain (σ / ε) in the elastic region of an engineering stress-strain diagram for a metal (E = σ/ε). (See page(s) 230, Sec. 5.3) |
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| Yield strength | the stress at which a specific amount of strain occurs in the engineering
tensile test. In the U.S. the yield strength is determined for 0.2 percent strain. (See page(s) 230, Sec. 5.3) |
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| Ultimate tensile strength (UTS) | the maximum stress in the engineering stress-strain
diagram. (See page(s) 230, Sec. 5.3) |
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| Hardness | a measure of the resistance of a material to permanent deformation. (See page(s) 230, Sec. 5.4) |
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| Slip | the process of atoms moving over each other during the permanent deformation of
a metal. (See page(s) 230, Sec. 5.5) |
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| Slipbands | line markings on the surface of a metal due to slip caused by permanent
deformation. (See page(s) 230, Sec. 5.5) |
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| Slip system | a combination of a slip plane and a slip direction. (See page(s) 230, Sec. 5.5) |
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| Deformation twinning | 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. (See page(s) 230, Sec. 5.5) |
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| Strain hardening (strengthening) | the hardening of a metal or alloy by cold working.
During cold working, dislocations multiply and interact, leading to an increase in the
strength of the metal. (See page(s) 230, Sec. 5.6) |
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| Solid-solution hardening (strengthening) | strengthening a metal by alloying additions
that form solid solutions. Dislocations have more difficulty moving through a metal
lattice when the atoms are different in size and electrical characteristics, as is the case
with solid solutions. (See page(s) 230, Sec. 5.7) |