Poisson's Ratio

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Poisson’s Ratio


one of the physical quantities characterizing an elastic solid. It is equal to the ratio of the absolute value of the lateral strain to the absolute value of the longitudinal strain and was introduced by S. D. Poisson.

Suppose a rectangular parallelepiped is stretched in the direction of the x-axis (Figure 1). The parallelepiped undergoes an elongation of ∈x = (a1a)/a > 0 along this axis and a contraction of ∈y = (b1b)/b < 0 and ∈z = (c1c)/c < 0 along the perpendicular y-axis and z-axis, respectively—in other words, its lateral cross section shrinks. Poisson’s ratio is equal to vyx = ǀ∈y ǀ/ǀ∈x ǀor vzx = ǀ∈zǀ/ǀcǀ.

Figure 1

In the case of an isotropic solid, Poisson’s ratio remains invariant if tension is replaced by compression or if the strain axes are changed—that is, vxy = νyx = vzx = v. Poisson’s ratio for anisotropic bodies is a function of the direction of the axes—that is, νxyvyxvzx. Poisson’s ratio, together with one of the moduli of elasticity, determines all the elastic properties of an isotropic solid. For most metals, Poisson’s ratio is close to 0.3.

poisson’s ratio

In a material under tension or compression, the absolute value of the ratio of transverse strain to the corresponding longitudinal strain.
References in periodicals archive ?
Consequently, Poisson's ratio is not expected to be constant and may increase or decrease with temperature and porosity in a manner that reflects how the dependence of E differs from that of B with respect to the variables T and [phi].
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In these studies, the mechanical properties concerning the longitudinal axis such as Young's modulus in the longitudinal direction, and the shear moduli and Poisson's ratios on the radial and tangential sections were examined, whereas the properties about the radial and tangential axes such as Young's modulus in the radial and tangential directions and the shear modulus and Poisson's ratio on the cross section were not examined.
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The inputs to this calculation were the meshed model from the MF/Flow analysis, Young's modulus parallel and perpendicular to flow, and Poisson's ratio.
3], elastic modulus is 2100 MPa, poisson's ratio is 0.
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By assuming a plane stress condition in the gauge section, Poisson's ratio v was determined by using Eq(s).
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