necking

metallurgy

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July 1, 2026

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In metallurgy, "necking" refers to a phenomenon observed during tensile testing of ductile materials. As a metal sample is stretched beyond its yield point, it begins to deform plastically. This deformation localizes in a specific region, causing the sample's cross-sectional area to significantly decrease, forming a "neck". This necking is a precursor to fracture, indicating the material's ability to undergo substantial plastic deformation before breaking. The extent of necking is often measured as elongation, a key mechanical property indicating ductility. The term "necking" can also refer to a narrow molding on a column or pilaster, or amorously kissing and caressing.12

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materials testing
Measures of ductility
…steel, for example, may “neck” (assume an hourglass shape) in response to stress. If the material is ductile, this local deformation is permanent, and the test piece does not assume its former shape if the stress is removed. With sufficiently high stress, fracture occurs.
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…steel, for example, may “neck” (assume an hourglass shape) in response to stress. If the material is ductile, this local deformation is permanent, and the test piece does not assume its former shape if the stress is removed. With sufficiently high stress, fracture occurs.
Read More