Poisson's Ratio of Aluminium

\nu_{\mathrm{Al}} = 0.33\ \text{—}

Value	0.33 —
Status	Measured: ± 0.01 — (0.03 relative)
Source	ASM Handbook, Vol. 2: Properties of Nonferrous Alloys
Categories	Material Properties Engineering & Trade

Poisson's Ratio of Aluminium in every dimensionless unit

part per trillion	330,000,000,000 ppt
part per billion	330,000,000 ppb
part per million	330,000 ppm
per cent mille	33,000 pcm
basis point	3,300 bp
per mille	330 per mille
percent	33 %
ratio	0.33 —

Learning zone

Aluminium contracts laterally by about a third of its axial strain, a shade more than steel. The number is close enough to steel's that swapping materials rarely changes a hand calculation, but it is what makes G come out at 26 GPa rather than 25.7, and it feeds the same strain-gauge, plate-bending and pressure-vessel relations.

Poisson's ratio is bounded for real isotropic materials between −1 and 0.5, and almost everything metallic lands between 0.25 and 0.35 — cork is famously near zero, rubber near 0.5, and engineered auxetic foams manage negative values by unfolding re-entrant cells. As with steel, this is an elastic-range value: plastic deformation is volume-conserving and drives the apparent ratio toward 0.5. Anisotropic materials such as rolled sheet, timber and composites have a different ratio for every pair of directions, so a single figure for them is a fiction.

Used by 3 solvers

Poisson's Ratio

\nu = \frac{\varepsilon_{lat}}{\varepsilon_{ax}}

Relation Between E, G and ν

E = 2G(1 + \nu)

Shear Modulus (G = τ/γ)

G = \frac{\tau}{\gamma}