Verified by Rachel Mayfield, Supply Chain Analyst - August 2026
Mild steel (low-carbon steel (S275, EN 1A family)): typical engineering properties at room temperature. These are representative handbook and datasheet values - composition, temper and product form move real figures, so for design work use the supplier's certified datasheet. For quick sizing, comparison and sanity checks, the table below is what you need.
Mild steel properties
| Property | Typical value | Unit |
|---|
| Density | 7,850 | kg/m3 |
| Melting range | 1,425-1,540 C | |
| Thermal conductivity | 50 | W/m K |
| Thermal expansion | 12 | x10-6 /K |
| Specific heat | 490 | J/kg K |
| Elastic modulus (E) | 210 | GPa |
| Tensile strength | 400-550 MPa (S275: min yield 275 MPa) | |
Where mild steel is used
Typical applications: general fabrication, structural sections, brackets, machine frames and the M-series fasteners covered across MLC's bolt and nut charts.
What to know before specifying it
Mild steel is the default engineering material: cheap, weldable, machinable and predictable. Its weaknesses are corrosion (paint, galvanise or plate it) and a strength ceiling well below alloy steels - property class 8.8 fasteners are already a stronger steel than S275 plate.