# Modulus of Rigidity

## Shear Modulus (Modulus of Rigidity) is the elasticity coefficient for shearing or torsion force.

Modulus of Rigidity - *G* - (Shear Modulus) is the coefficient of elasticity for a shearing force. It is defined as

- "the ratio of shear stress to the displacement per unit sample length (shear strain)"

Modulus of Rigidity can be experimentally determined from the slope of a stress-strain curve created during tensile tests conducted on a sample of the material.

The definition of Modulus of Rigidity:

- the ratio of shear stress to the displacement per unit sample length (shear strain)

### Modulus of Rigidity of some Common Materials

Material | Shear Modulus - G -( GPa)(10^{6} psi) |
---|---|

Aluminum Alloys | 27 |

Aluminum, 6061-T6 | 24 |

Aluminum, 2024-T4 | 28 |

Beryllium Copper | 48 |

Brass | 40 |

Bronze | 44.8 |

Cadmium | 19 |

Carbon Steel | 77 |

Cast Iron | 41 |

Chromium | 115 |

Concrete | 21 |

Copper | 45 |

Glass | 26.2 |

Glass, 96% silica | 19 |

Inconel | 79 |

Iron, Ductile | 63 - 66 |

Iron, Malleable | 64 |

Kevlar | 19 |

Lead | 13.1 |

Magnesium | 16.5 |

Molybdenum | 118 |

Monel metal | 66 |

Nickel Silver | 48 |

Nickel Steel | 76 |

Nylon | 4.1 |

Phosphor Bronze | 41 |

Plywood | 0.62 |

Polycarbonate | 2.3 |

Polyethylene | 0.12 |

Rubber | 0.0003 |

Structural Steel | 79.3 |

Stainless Steel | 77.2 |

Steel, Cast | 78 |

Steel, Cold-rolled | 75 |

Tin | 18 |

Titanium, Grade 2 | 41 |

Titanium, Grade 5 | 41 |

Titanium, 10% Vanadium | 42 |

Tungsten | 161 |

Wood, Douglas Fir | 13 |

Zinc | 43 |

Z-nickel | 76 |

*1 GPa = 10*^{9}Pa = 0.145 x 10^{6}psi (lb_{f}/in^{2})*1 x 10*^{6}psi = 6.9 GPa