Baustahl
Structural steels are among the most widely used engineering materials overall. They are used in mechanical engineering, construction, the automotive industry, and the energy sector for the production of components that must withstand mechanical stress, compression, tension, bending, and torsion.
🧩 Characteristics
Good strength, toughness, and formability
Excellent weldability and machinability
Possibility of heat treatment (improving strength, hardness, and elasticity)
Low alloying element content → cost-effective production
Supplied in various conditions: hot-rolled, normalized, quenched and tempered
⚙️ Applications
Load-bearing and supporting structures (columns, beams, frames, bridges)
Automotive parts, shafts, pins, bolts, nuts, transmission components
Tubes, profiles, sheets, bars, strips
Welds and welded structures
Thermal Properties of Structural Steel (Typical Values)
| Property | Symbol | Value (typical) | Unit | Note |
|---|---|---|---|---|
| Thermal conductivity | λ | 45 – 60 | W/m·K | depends on chemical composition |
| Coefficient of thermal expansion | α | 10 – 13 ×10⁻⁶ | 1/K | important for dimensional stability |
| Specific heat capacity | c | 460 – 500 | J/kg·K | ability to store heat |
| Melting temperature | — | 1420 – 1520 | °C | depends on steel grade |
| Service temperature (long-term) | — | up to approx. 400–500 | °C | above this, strength decreases significantly |
🧠 Interesting fact
Structural steel has an interesting property – when heated, it first expands significantly, but at higher temperatures it rapidly loses strength.
For example, at around 500–600 °C, it can lose more than half of its load-bearing capacity. That is why steel structures in buildings are protected with special fire-resistant coatings or cladding.
