Structural steel S355K2 (material number 1.0596)

Quality	Standard	Material No.	Past names
S355K2	DIN EN 10025-2	1.0596	S355K2G3

Quality

Testing direction	Yield strength R_eH (MPa) ≤ 16 mm	Yield strength R_eH (MPa) > 16 ≤ 40 mm	Tensile strength R_m (MPa) < 3 mm	Tensile strength R_m (MPa) ≥ 3 mm ≤ 100 mm
Transversal (≥ 600mm)	≥ 355	≥ 345	510 – 680	470 – 630

Mechanical properties at room temperature: yield strength and tensile strength

Sample direction a	Elongation A₈₀ (in %) ≤ 1 mm	A₈₀ (in %) > 1 ≤ 1,5 mm	A₈₀ (in %) > 1,5 ≤ 2 mm	A₈₀ (in %) > 2 ≤ 2,5 mm	A₈₀ (in %) > 2,5 ≤ 3 mm	A_5,65 (in %) > 3 ≤ 40 mm
l	≥ 14	≥ 15	≥ 16	≥ 17	≥ 18	≥ 22
t	≥ 12	≥ 13	≥ 14	≥ 15	≥ 16	≥ 20

Mechanical properties at room temperature: Elongation

C % ≤ 16 mm	C % >16 mm ≤ 40 mm	Si %	Mn %	P %	S %	N %	Cu %	CEV % ≤ 30 mm
≤ 0,20	≤ 0,20	≤ 0,55	≤ 1,60	≤ 0,025	≤ 0,025	–	≤ 0,55	≤ 0,45

Chemical composition according to melt analysis

Temperature	Minimum impact energy KV₂ (J) ≤ 150 mm
-20°C	40

Impact strength KV2 on longitudinal specimens

Structural Steel S355K2 – The high-end toughness grade for extreme conditions

Superior resistance to brittle fracture at low temperatures in heavy steel construction
The unalloyed quality steel S355K2 represents the highest toughness grade within the 355 strength class according to DIN EN 10025-2. Wherever components are exposed to extreme dynamic forces, sudden loads, or arctic temperatures, this flat steel product—available in nominal thicknesses up to 30 mm—provides a crucial safety margin. It is the specialist choice for highly stressed structures in the offshore sector, heavy machinery manufacturing, and materials handling technology.

Technical Specifications and Mechanical Profile

Outstanding impact toughness (grade K2): The key characteristic of S355K2 is its extreme toughness. It guarantees an impact energy of at least 40 joules at a test temperature of -20 °C. This significantly exceeds the requirements of the J2 grade and minimizes the risk of cracking under full load in sub-zero temperatures.

Strength Properties: Like the sister grades, it offers a minimum yield strength of 355 MPa (for thicknesses greater than 16 mm) or 345 MPa (for thicknesses up to 30 mm).

Killed high-quality steel: The material is cast in a fully killed state and has a particularly fine-grained, homogeneous microstructure with high resistance to aging.

Customized Configuration for Your Project

Variable Delivery Condition: We deliver flat products exactly in the delivery condition specified by you or your customer—whether as-rolled (+AR), thermomechanically rolled (+M), or normalized (+N).

Advanced Testing and Options: For safety-critical applications, all standard technical specifications can be flexibly agreed upon. You can optionally order the material with specific test certificates for each individual rolled sheet, with optimal suitability for cold forming (bending), or with a specific chemical composition for subsequent galvanizing.