--- title: "1.8966 — Weathering steels" description: "1.8966 is the material number of the grade also listed as S355K2G1W. Category: Weathering steels. Designations recorded for this grade: 5." canonical: https://steelequivalents.com/materials/material-no/1.8966 language: en robots: index, follow og_type: website type: material-detail language_alternates: en: https://steelequivalents.com/materials/material-no/1.8966.md cs: https://steelequivalents.com/cs/materiály/číslo-materiálu/1.8966.md de: https://steelequivalents.com/de/werkstoffe/werkstoff-nr/1.8966.md es: https://steelequivalents.com/es/materiales/número-de-material/1.8966.md fr: https://steelequivalents.com/fr/matériaux/numéro-de-matériau/1.8966.md hu: https://steelequivalents.com/hu/anyagok/anyagszám/1.8966.md it: https://steelequivalents.com/it/materiali/numero-materiale/1.8966.md nl: https://steelequivalents.com/nl/materialen/materiaalnummer/1.8966.md pl: https://steelequivalents.com/pl/materiały/numer-materiału/1.8966.md pt: https://steelequivalents.com/pt/materiais/número-do-material/1.8966.md ru: https://steelequivalents.com/ru/материалы/номер-материала/1.8966.md tr: https://steelequivalents.com/tr/malzemeler/malzeme-numarası/1.8966.md zh: https://steelequivalents.com/zh/材料/材料编号/1.8966.md ja: https://steelequivalents.com/ja/材料/材料番号/1.8966.md ar: https://steelequivalents.com/ar/المواد/رقم-المادة/1.8966.md ko: https://steelequivalents.com/ko/재료/재료번호/1.8966.md pt-br: https://steelequivalents.com/pt-br/materiais/número-do-material/1.8966.md hi: https://steelequivalents.com/hi/सामग्री/सामग्री-संख्या/1.8966.md content_hash: sha256:680d20ae43101941ca4c302619fb07785ad9c4172ab2bc26665eacd0241e30ec generated: 2026-09-24 --- > **Machine-readable Markdown rendering.** This is a Markdown representation of a web page, > served for AI agents and crawlers as a token-efficient alternative to the full HTML. > Full interactive HTML version: https://steelequivalents.com/materials/material-no/1.8966 > Canonical URL: https://steelequivalents.com/materials/material-no/1.8966 > Available languages: en, cs, de, es, fr, hu, it, nl, pl, pt, ru, tr, zh, ja, ar, ko, pt-br, hi > Change detection: `content_hash` is the SHA-256 of this document's Markdown body — everything > below this block, whitespace-trimmed, excluding the front-matter. Compare it to detect a real > content change; `generated` moves on every render and is not a change signal. Material number · Europe · 5 designations # 1.8966 1.8966 is the material number of the grade also listed as S355K2G1W. It is a material in the category Weathering steels. We list 5 designations recorded for this grade, in the standards DIN / EN, AISI / SAE and AFNOR. - ***Material no.* **1.8966**** - [*Category* **Weathering steels · 27 grades**](/categories/weathering-steels "Category: Weathering steels · 27 grades") - *Designations* **5** [Search](/search "Steel grade search")[Inquiry](/inquiry?material=592b9082-c137-4086-a862-176b4f6510f5 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/material-no/1.8966.pdf "Datasheet as PDF") ## About Weathering steels Weathering steels are structural steels designed to develop a protective patina when exposed to the atmosphere. This characteristic helps limit further corrosion and makes them suitable for bridges, building facades, rail vehicles and other outdoor structures where reduced coating maintenance is desirable. This describes the material class as a whole. Always confirm the individual grade against the standard before ordering. ## Also known as 5 designations · 3 standards · nothing hidden This grade’s own name recorded in our sources as this grade’s own designation under that standard. Indicative taken from a published cross-reference table; a close match, not a guarantee of interchangeability. Verify against the mill certificate before ordering. Withdrawn designation no longer current — a separate column from the two above, so a name can be same grade and withdrawn at once. DIN / EN Europe · 3 - [S355K2G1W This grade’s own name Withdrawn](/materials/din-en/s355k2g1w "DIN / EN S355K2G1W") - [S355K2W This grade’s own name Withdrawn](/materials/din-en/s355k2w "DIN / EN S355K2W") - [S355K2W(+N) Indicative](/materials/din-en/s355k2w-n "DIN / EN S355K2W(+N)") AISI / SAE United States · 1 - [A709Gr.50W Indicative](/materials/aisi-sae/a709gr-50w "AISI / SAE A709Gr.50W") AFNOR France · 1 - [E36WB4 Indicative](/materials/afnor/e36wb4 "AFNOR E36WB4") Every designation on file is listed — no truncation, no “+ n more”. Each one is itself a route that leads back here. ## Chemical composition 14 elements on file · weight % What this alloy is Fe Mn Ni Cr Iron — the balance, never listed by a standard — 96 % Mn — 1 % Ni — 0.7 % Cr — 0.6 % Traces & impurities · 1.8 % Logarithmic scale, 0.01 % to 100 % — every value here compares directly, decade by decade. | Element | % by weight | |---|---| | C | ≤ 0.16 | | Si | ≤ 0.5 | | Mn | 0.5–1.5 | | P | 0.035 | | S | 0.035 | | Cr | 0.4–0.8 | | Mo | ≤ 0.3 | | Ni | 0.65 | | V | 0.02–0.12 | | Cu | 0.25–0.55 | | Al | ≥ 0.02 | | Ti | 0.02–0.1 | | Nb | 0.015–0.06 | | Zr | ≤ 0.15 | Carbon Silicon Manganese Phosphorus Sulfur Chromium Molybdenum Nickel Vanadium Copper Aluminium Titanium Niobium Zirconium 0.01 % 0.1 % 1 % 10 % 100 % The scale is logarithmic, not the element’s raw share of the alloy — the only honest way to fit 0.01 % and 100 % in one picture, and it means every value here can be compared with every other. | Element | As published source text, verbatim | Min% by weight | Max% by weight | Bound | |---|---|---|---|---| | C | ≤0,16 | — | 0.160 | Max | | Al | ≥0,020 | 0.020 | — | Min | | Si | ≤0,50 | — | 0.500 | Max | | P | 0,035 | 0.035 | 0.035 | Exact | | S | 0,035 | 0.035 | 0.035 | Exact | | Ti | 0,02-0,10 | 0.020 | 0.100 | Range | | V | 0,02-0,12 | 0.020 | 0.120 | Range | | Cr | 0,40-0,80 | 0.400 | 0.800 | Range | | Mn | 0,50-1,50 | 0.500 | 1.500 | Range | | Ni | 0,65 | 0.650 | 0.650 | Exact | | Cu | 0,25-0,55 | 0.250 | 0.550 | Range | | Zr | ≤0,15 | — | 0.150 | Max | | Nb | 0,015-0,060 | 0.015 | 0.060 | Range | | Mo | ≤0,30 | — | 0.300 | Max | The published column is the source string byte-for-byte, decimal comma and all; Min and Max are the parsed bounds. Elements not listed have no value on file — they are omitted, never inferred. ## Predicted transformation temperatures computed from composition · °C Predicted Ae3 814 °C Predicted Ae1 722 °C Predicted Acm 423 °C Predicted Bs 526 °C These four temperatures are a CALCULATION from this grade's own composition, using the published Li, Niebuhr, Meekisho & Atteridge (1998) model — never a measurement, and computed from the UPPER BOUND of each element's specified range, not a mid-range figure. Where this grade also has a measured transformation point (Ac1, Ac3, Ar1, Ar3) on file, it is shown separately, in Physical & mechanical properties, and is never replaced by the predicted figures here — Ae (predicted, equilibrium) and Ac/Ar (measured, on heating or cooling) are different physical quantities and can differ by tens of degrees; a mismatch between the two is not an error in either. ## Physical & mechanical properties Density 7,85 g/cm³ Exact An absent property means we hold no value for it — it is left out rather than estimated, interpolated from a neighbouring grade, or filled from a handbook. It does not mean the property is undefined for the material. ## Properties by condition 1 conditions · 16 values By thickness**no delivery state stated** source `steelnumber` | Thickness mm | ReH N/mm² | Rm N/mm² | A80% | A% | |---|---|---|---|---| | 1.5 – 2 | — | — | 16 | — | | 2 – 2.5 | — | — | 17 | — | | 2.5 – 3 | — | — | 18 | — | | ≤ 3 | — | 510 – 680 | — | — | | 3 – 100 | — | 470 – 630 | — | — | | 3 – 40 | — | — | — | 22 | | ≤ 16 | 355 | — | — | — | | 16 – 40 | 345 | — | — | — | | 40 – 63 | 335 | — | — | 21 | | 63 – 80 | 325 | — | — | — | | 63 – 100 | — | — | — | 20 | | 80 – 100 | 315 | — | — | — | | 100 – 150 | 295 | 450 – 600 | — | 18 | Every figure holds only for the condition on its own row. Values are never merged across conditions or across sources, never averaged, and never interpolated between two rows. An em dash means no value on file — never zero. Figures are converted to the unit in the column header; the source’s own wording is kept and shown where the two differ. ## Similar grades — and why Selection rule, stated so you can disagree with it: same number class 1.8, a shared category, and a published range for Mn / Ni that overlaps this grade’s. These are neighbours in composition space — they are not equivalents, and none is claimed to be interchangeable with this grade. [A709-50W 1.8959 Mn 0,50-1,50 · Ni (0,65) - ΔMn 0.00 - ΔNi 0.00 - 23 designations](/materials/din-en/a709-50w "A709-50W")[A600C 1.8963 Mn 0,50-1,50 · Ni 0,65 - ΔMn 0.00 - ΔNi 0.00 - 29 designations](/materials/din-en/a600c "A600C")[S355J2W 1.8965 Mn 0,50-1,50 · Ni (0,65) - ΔMn 0.00 - ΔNi 0.00 - 8 designations](/materials/din-en/s355j2w "S355J2W")[S355K2W 1.8967 Mn 0,50-1,50 · Ni (0,65) - ΔMn 0.00 - ΔNi 0.00 - 3 designations](/materials/din-en/s355k2w "S355K2W")[9CrNiCuP324 1.8945 Mn ≤1,00 · Ni (0,65) - ΔMn 0.50 - ΔNi 0.00 - 37 designations](/materials/din-en/9crnicup3-2-4 "9CrNiCuP324")[Fe510D1KI 1.8946 Mn ≤1,00 · Ni (0,65) - ΔMn 0.50 - ΔNi 0.00 - 7 designations](/materials/din-en/fe510d1ki "Fe510D1KI") ## Looking for this grade under another name? Search the catalogue by designation, material number or composition — every name on this page is itself a way in. [Search](/search "Steel grade search")[Inquiry](/inquiry?material=592b9082-c137-4086-a862-176b4f6510f5 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/material-no/1.8966.pdf "Datasheet as PDF")