Solids and Metals - Speed of Sound
Speed of sound in solids and metals like aluminum, brass, concrete and more.
Speed of sound in normal air is 343 m/s. In water the speed of sound is 1433 m/s. Speed of Sound in some common solids are indicated in the table below. Note that propagation velocities varies with frequencies.
| Solid | Speed of Sound (m/s) | ||
|---|---|---|---|
| Longitudinal | Shear | Extensional | |
| Aluminum, rolled | 6420 | 3040 | 5000 |
| Antimony | 3400 | ||
| Beryllium | 12890 | 8880 | 12870 |
| Bismut | 2180 | 1790 | |
| Brass (70% Cu, 30% Zn) | 4700 | 2110 | 3480 |
| Brick | 4200 | 3600 | |
| Cadmium | 2780 | 2400 | |
| Concrete | 3700 | 3200 | |
| Constantan | 5177 | 2625 | 4270 |
| Copper, annealed | 4760 | 2325 | 3810 |
| Copper, rolled | 5010 | 2270 | 3750 |
| Cork | 518 | 366 | |
| Diamond | 12000 | ||
| Duralumin | 6320 | 3130 | 5150 |
| Glass, heavy silicate flint | 3980 | 2380 | 3720 |
| Glass, light borate crown | 5100 | 2840 | 4540 |
| Glass, pyrex | 5640 | 3280 | 5140 |
| Gold, hard drawn | 3240 | 1200 | 2030 |
| Granite | 5950 | ||
| Iridium | 4790 | ||
| Iron, cast | 4994 | 2809 | 4480 |
| Iron, electrolytic | 5950 | 3240 | 5120 |
| Ivory | 3010 | ||
| Lead, annealed | 2160 | 700 | 1190 |
| Lead, rolled | 1960 | 690 | 1210 |
| Lucite | 2680 | 1100 | 1840 |
| Magnesium, annealed | 5770 | 3050 | 4940 |
| Manganese | 4660 | 3830 | |
| Marble | 3810 | ||
| Molybdenum | 6250 | 3350 | 5400 |
| Monel | 5350 | 2720 | 4400 |
| Nickel | 6040 | 3000 | 4900 |
| Nylon 6/6 | 2620 | 1070 | 1800 |
| Platinum | 3260 | 1730 | 2800 |
| Polyethylene | 1950 | 540 | 920 |
| Polystyrene | 2350 | 1120 | 1840 |
| Rubber, butyl | 1830 | ||
| Rubber, gum | 1550 | ||
| Rubber, neoprene | 1600 | ||
| Silica, fused | 5968 | 3764 | 5760 |
| Silver | 3650 | 1610 | 2680 |
| Slate | 4510 | ||
| Steel (1% C) | 5940 | 3220 | 5180 |
| Steel, stainless | 5790 | 3100 | 5000 |
| Tantalium | 3350 | ||
| Tin, rolled | 3320 | 1670 | 2730 |
| Titanium | 6070 | 3125 | 5090 |
| Tungsten, annealed | 5220 | 2890 | 4620 |
| Tungsten, drawn | 5410 | 2640 | 4320 |
| Tungsten carbide | 6655 | 3980 | 6220 |
| Wood (hard) | 3960 | ||
| Wood, longitudinal parallel with grain | 3300 - 5000 | ||
| Zinc, rolled | 4210 | 2440 | 3850 |
- 1 m/s = 3.6 km/h = 196.85 ft/min = 3.28 ft/s = 2.237 mph
In a liquid or gas only one speed is required. In an isotropic solid sound speed is characterized by
- speed of longitudinal waves in infinite elements (elements much larger than the wavelength of the sound)
- speed of shear waves in infinite elements
- speed of extensional waves along a rod (with diameter much smaller than the wavelength)
In wood the speed of sound varies with grain direction because the transverse modulus of elasticity is as little as 1/20 the longitudinal value. The speed of sound across the grain is about one-fifth to one-third of the longitudinal value. There is no recognized independent effect of species of wood on the speed of sound. Variability in the speed of sound relates to the variability of modulus of elasticity and density.
Note that speed is a scalar quantity. Velocity is vector quantity with direction.
