S355K2
Data verifiedS355K2 is the high-toughness quality of S355 to EN 10025-2. Where S355J2 guarantees 27 J at −20 °C, K2 raises the bar to 40 J at −20 °C, which designers use for fracture-sensitive, dynamically loaded or thick welded structures.
Chemical composition
| Element | Content (%) |
|---|---|
| C | ≤0.20 |
| Si | ≤0.55 |
| Mn | ≤1.60 |
| P | ≤0.025 |
| S | ≤0.025 |
| Cu | ≤0.55 |
Weight percent, per the governing standard ranges. Actual values per heat are on the mill certificate.
Properties
| Yield strength | ≥355 MPa (≤16 mm) |
| Tensile strength | 470–630 MPa |
| Impact | 40 J at −20 °C |
| Density | 7.85 g/cm³ |
Heat treatment
Supplied as-rolled or normalized; chemistry matches S355J2 — the K2 quality is a toughness upgrade, not a chemistry change.
Equivalent grades
| Standard | Designation |
|---|---|
| din | 1.0596 (S355K2) |
| aisi | A572 Gr.50 (near) |
| jis | SM520C (near) |
| gb | Q355D class (near) |
Compare side by side: S355K2 vs S355J2 · S355K2 vs S355J0 · S355K2 vs Q355D
Equivalents overlap in chemistry and use but are not always identical — see our equivalents guide before substituting in certified designs.
Applications & Processing
Applications: Bridges, offshore and crane structures, heavy welded nodes, dynamically loaded fabrications.
Processing: Same welding practice as S355J2; specify K2 where the design code or the client asks for the higher Charpy energy at −20 °C.
FAQ
- What does K2 mean in S355K2?
- K denotes the higher impact-energy class: 40 J instead of 27 J, tested at −20 °C (the “2”). Chemistry and strength are the same as S355J2.
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Ask for a quotationVisit NasteelSource: EN 10025-2 published ranges · Last updated 2026-11-03. Data is indicative — verify critical values against the governing standard and mill certificate before use.