Metals and Alloys - Bulk Modulus Elasticity
The Bulk Modulus - resistance to uniform compression - for some common metals and alloys.
The Bulk Modulus Elasticity - or Volume Modulus - is a measure of the substance's resistance to uniform compression.
Bulk Modulus of Elasticity is the ratio of stress to the change in volume in a material subjected to axial loading.
Typical values of bulk modulus for some metals and alloys are indicated below. Note that the values may vary widely.
| Material | Bulk Modulus - K - | |
|---|---|---|
| (106 psi) | (GPa) | |
| Aluminum, various alloys | 9.9 - 10.2 | 68 - 70 |
| Boron Carbide (B4) | 29 - 34.8 | 200 - 240 |
| Brass, 70-30 | 15.7 | 108 |
| Brass, cast | 16.8 | 116 |
| Concrete | 0.87 - 4.1 | 6 - 28 |
| Copper | 17.9 | 123 |
| Diamond (carbon) | 80 - 93 | 550 - 640 |
| Iron, cast | 8.4 - 15.5 | 58 - 107 |
| Iron, malleable | 17.2 | 119 |
| Magnesium alloy | 4.8 | 33.1 |
| Monel metal | 22.5 | 155 |
| Phosphor bronze | 16.3 | 112 |
| Silver | 13.9 - 15.4 | 96 - 106 |
| Stainless Steels (18-8) | 23.6 | 163 |
| Steel, cast | 20.2 | 139 |
| Steel, cold rolled | 23.1 | 159 |
| Steel, various | 22.6 - 24.0 | 156 - 165 |
| Tin | 6.1 - 8.4 | 42 - 60 |
| Tungsten | 44.5 - 15.5 | 307 - 314 |
- 1 GPa = 109 Pa (N/m2)
- 1 GPa = 0.145 psi
Stainless steel with Bulk Modulus 163×109 Pa is approximate 80 times harder to compress than water with Bulk Modulus 2.15×109 Pa.
Bulk Modulus is related to Modulus of Elasticity and Poisson's Ratio as
K = E / 3 (1 - 2 r) (1)
where
K = Bulk Modulus (Pa (N/m2), psi (lbf/in2)
E = Modulus of Elasticity (Pa (N/m2), psi (lbf/in2)
r = Poisson's Ratio
