Electrical Resistivity of Carbon Steel
| Value | 1.6e-7 Ω·m |
| Status | Measured: ± 4.00e-08 Ω·m (0.25 relative) |
| Source | ASM Handbook, Vol. 1 / CRC Handbook of Chemistry and Physics |
| Categories | Material PropertiesEngineering & Trade |
| nanoohm meter | 160 nΩ·m |
| ohm circular mil per foot | 96.244879 Ω·cmil/ft |
| microohm centimeter | 16 μΩ·cm |
| microohm meter | 0.16 μΩ·m |
| ohm square millimeter per meter | 0.16 Ω·mm²/m |
| milliohm centimeter | 0.016 mΩ·cm |
| ohm centimeter | 0.000016 Ω·cm |
| ohm meter | 1.6000000e-07 Ω·m |
| kiloohm centimeter | 1.6000000e-08 kΩ·cm |
| megaohm centimeter | 1.6000000e-11 MΩ·cm |
Learning zone
Steel is a mediocre conductor: an order of magnitude worse than copper, and far more variable, because carbon, manganese and alloying additions all scatter electrons. Values from 1.0 to 2.0 × 10⁻⁷ Ω·m are all legitimately "steel". Stainless is worse still at about 7.2 × 10⁻⁷ Ω·m, roughly 43 times copper.
This is exactly why steel is used where you want resistance and not where you want conduction. Resistance heating elements, induction-heated workpieces and resistance spot welding all exploit it; ACSR transmission cable puts a steel core inside aluminium strands purely for tensile strength and expects it to carry little current. The magnetic complication matters too: steel is ferromagnetic, so at power frequencies skin effect and hysteresis make its effective AC resistance much higher than the DC value — which is why a steel conduit carrying only one phase of a circuit heats up, and why the NEC requires all conductors of a circuit in the same ferrous raceway.