Shear Modulus of Aluminium Alloy

GAl=2.6×1010 PaG_{\mathrm{Al}} = 2.6 \times 10^{10}\ \text{Pa}
Value2.6e10 Pa
StatusMeasured: ± 1,000,000,000 Pa (0.038 relative)
SourceAluminum Design Manual (The Aluminum Association)
CategoriesMaterial PropertiesEngineering & Trademechanics
G_Al in every pressure unit
pascal26,000,000,000 Pa
kilopascal26,000,000 kPa
megapascal26,000 MPa
bar260,000 bar
atmosphere256,600.05 atm
millimeter of mercury195,016,010 mmHg
pound per square inch3,770,981.2 psi
foot of water column8,698,366.7 ft H₂O
gigapascal26 GPa
kip per square inch3,770.9812 ksi
inch of mercury7,677,795.7 inHg
inch of water column104,380,400 in w.g.

Learning zone

Applying G = E / [2(1 + ν)] with E = 68.9 GPa and ν = 0.33 gives 25.9 GPa, and handbooks quote 26 GPa (3.8 × 10⁶ psi) for the 5000, 6000 and 7000 series alike. As with Young's modulus, temper and alloy move it by a couple of percent at most.

Aluminium's low shear modulus is a bigger practical problem than its low Young's modulus, because aluminium sections are typically thin-walled extrusions and thin walls are what torsion and shear buckling punish. A 6061 open channel resisting torque twists roughly three times as much as an identical steel one; shear-buckling and web-crippling checks that are formalities in steel become governing limit states in aluminium. Treat this value as isotropic room-temperature wrought material — castings are lower and less consistent, and everything softens above about 150 °C.