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n value
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“A term commonly referred to as work-hardening exponent derived from the relationship between true stress and true strain given by =K n.
Often called work strengthening exponent and in mechanical nomenclature may be called “m” (Automotive Steel Partnership, 1991, p. 11).
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necking
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(1) The reduction of the crosssectional area of metal in a localized area by uniaxial tension or by stretching. (2) The reduction of the
diameter of a portion of the length of a cylindrical shell or tube. See Figure N1 for an example of necking. The onset of localized necking is dependent upon the stress state which is affected by geometrical factors.
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nest
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(1) To stack like parts within one another to occupy a minimum space. (2) A plate having an opening to conform to the contour of a part used to
locate the part in a die. (3) To lay out a blank so that the outlines of parts produced will interlock with each following and each preceding part and require the minimum amount of material.
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nesting
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The process of accurately locating and holding the part in a die or fixture by using gages or the part's form.
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nitrogen die cylinder
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See gas cylinder.
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nitrogen pressure
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“The nitrogen pressure in cylinders which are used to cushion the dies (Automotive Steel Partnership, 1991, p. 11).
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no stock movement
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On progressive dies this is the bottom portion of the press stroke during which the . coil feed cannot move the strip.
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noise factors
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“Factors that can potentially affect the quality characteristic but cannot be controlled at the design phase” (Moen, R. D., Nolan, T. W., Provost,
L. P., 1991, p.405).
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noise variable
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“See background variable” (Moen, R. D., Nolan, T. W., Provost, L. P., 1991, p.402).
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normal anisotropy
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(See Figure N2) 
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normalizing
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A process of heating the steel above the critical temperature and cooling it freely in air. It is a special case of annealing.
Normalizing does leave the metal in a uniform, unstressed condition but may not -leave it machinable. See annealing.
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notching
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The cutting out of various shapes from the edge of a strip, blank, or part.
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nuisance variable
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“An unknown background variable that can affect a response variable in an experiment, sometimes called a lurking variable or extraneous variable”
(Moen, R. D., Nolan, T. W., Provost, L. P., 1991, p.405).
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nutter die
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A die that incorporates nutter units to clinch nuts into sheet metal parts.
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n-value
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See strain-hardening exponent.
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