Unalloyed structural steel for general and more demanding applications
Steel grade 1.0570 (S355, ČSN 11 523) is one of the most widely used structural steels in Europe. It is known for its excellent weldability, consistent mechanical properties, and good strength combined with relatively easy machining.
It is suitable for welded, formed, and machined parts, steel structures, and components subjected to medium stress.
Properties of steel 1.0570 (S355)
🔩 Strength and reliability
Minimum yield strength of 355 MPa. A robust structural steel suitable for construction parts, frames, beams, and components under medium load.
🔧 Good machinability
Good machining properties in turning, milling, and sawing. Especially suitable for the production of larger components.
🔥 Limited heat treatment
This steel is not intended for hardening. Except for normalizing, heat treatment is generally not applied.
🛠️ Excellent weldability
Its low carbon content allows easy welding without an increased risk of cracking.
📦 Consistent mechanical properties
A reliable structural steel for use in industrial, engineering, and steel construction applications.
Chemical composition 1.0570 (S355, 11 523)
| Element | Content (%) |
|---|---|
| C | ≤ 0.22 |
| Mn | 1.00 – 1.60 |
| Si | ≤ 0.55 |
| P | ≤ 0.040 |
| S | ≤ 0.040 |
| N | ≤ 0.012 |
| Cu | ≤ 0.55 |
Typical applications of steel 1.0570
🏗️ Steel and construction structures
beams, columns, frames
welded structures
stiffening and connecting elements
🛠️ Mechanical engineering
less heavily loaded parts
brackets, holders, flanges
shafts with low stress load
🚛 Automotive and parts manufacturing
basic structural components
chassis parts with low load
🧱 General structural applications
railings, platforms, support frames
steel elements requiring strength and weldability
Heat treatment (guideline values)
| Process | Temperature | Note |
|---|---|---|
| Normalizing | 880 – 940 °C | improves toughness and homogenizes the structure |
| Hardening | not recommended | structural steel without significant hardenability |
| Tempering | – | generally not applied |
| Welding | without preheating at standard thicknesses | low carbon content = excellent weldability |
Typical mechanical properties
Yield strength Re: ≥ 355 MPa
Tensile strength Rm: 470 – 630 MPa
Elongation A: 22 – 24%
Hardness: approx. 130–180 HB, depending on delivery condition and material thickness
