--- title: "NW9911 — High-temperature steels" description: "NW9911 in ISO: material number 2.4975, also listed as NiFeCr12Mo. Category: High-temperature steels. Designations recorded for this grade: 7." canonical: https://steelequivalents.com/materials/iso/nw9911 language: en robots: index, follow og_type: website type: material-detail language_alternates: en: https://steelequivalents.com/materials/iso/nw9911.md cs: https://steelequivalents.com/cs/materiály/iso/nw9911.md de: https://steelequivalents.com/de/werkstoffe/iso/nw9911.md es: https://steelequivalents.com/es/materiales/iso/nw9911.md fr: https://steelequivalents.com/fr/matériaux/iso/nw9911.md hu: https://steelequivalents.com/hu/anyagok/iso/nw9911.md it: https://steelequivalents.com/it/materiali/iso/nw9911.md nl: https://steelequivalents.com/nl/materialen/iso/nw9911.md pl: https://steelequivalents.com/pl/materiały/iso/nw9911.md pt: https://steelequivalents.com/pt/materiais/iso/nw9911.md ru: https://steelequivalents.com/ru/материалы/iso/nw9911.md tr: https://steelequivalents.com/tr/malzemeler/iso/nw9911.md zh: https://steelequivalents.com/zh/材料/iso/nw9911.md ja: https://steelequivalents.com/ja/材料/iso/nw9911.md ar: https://steelequivalents.com/ar/المواد/iso/nw9911.md ko: https://steelequivalents.com/ko/재료/iso/nw9911.md pt-br: https://steelequivalents.com/pt-br/materiais/iso/nw9911.md hi: https://steelequivalents.com/hi/सामग्री/iso/nw9911.md content_hash: sha256:9778db6a193c716dd9227645b1c82e2fc7804895d31b7066c71d9c2ea3840b3d 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/iso/nw9911 > Canonical URL: https://steelequivalents.com/materials/iso/nw9911 > 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. ISO · International · 7 designations # NW9911 NW9911 is a designation in ISO for the material held under material number 2.4975, also listed as NiFeCr12Mo. It is a material in the category High-temperature steels. We list 7 designations recorded for this grade, in the standards DIN / EN, AISI / SAE, BS, ISO and GB. - [*Material no.* **2.4975**](/materials/material-no/2.4975 "Material no.: 2.4975") - [*Category* **High-temperature steels · 40 grades**](/categories/high-temperature-steels "Category: High-temperature steels · 40 grades") - *Designations* **7** [Search](/search "Steel grade search")[Inquiry](/inquiry?material=c0023c59-0217-47ae-bda1-acbfa1bb7b53&designation=0db4ee72-574d-478e-a4f5-63b960200778 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/iso/nw9911.pdf "Datasheet as PDF") ## If you came for one of these The most-used names for this grade. - [DIN / EN NiFeCr12Mo This grade’s own name](/materials/din-en/nifecr12mo "DIN / EN NiFeCr12Mo") - [AISI / SAE 681 This grade’s own name](/materials/aisi-sae/681 "AISI / SAE 681") ## About High-temperature steels High-temperature steels are steels designed to retain useful strength and structural stability during exposure to elevated temperatures. Their alloying systems provide resistance to oxidation, creep and loss of mechanical properties during prolonged heating, making them suitable for furnace components, heat exchangers, boilers and other hot-service equipment. This describes the material class as a whole. Always confirm the individual grade against the standard before ordering. ## Also known as 7 designations · 5 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 · 1 - [NiFeCr12Mo This grade’s own name](/materials/din-en/nifecr12mo "DIN / EN NiFeCr12Mo") AISI / SAE United States · 1 - [681 This grade’s own name](/materials/aisi-sae/681 "AISI / SAE 681") BS United Kingdom · 1 - [HR53 Indicative](/materials/bs/hr53 "BS HR53") ISO International · 2 - [NiFe36Cr12Mo6Ti3 Indicative](/materials/gb/nife36cr12mo6ti3 "ISO NiFe36Cr12Mo6Ti3") - **NW9911 Indicative** GB China · 2 - [NiFe36Cr12Mo6Ti3 Indicative](/materials/gb/nife36cr12mo6ti3 "GB NiFe36Cr12Mo6Ti3") - [NW99911 Indicative](/materials/gb/nw99911 "GB NW99911") Every designation on file is listed — no truncation, no “+ n more”. Each one is itself a route that leads back here. ## Chemical composition 12 elements on file · weight % What this alloy is Fe Ni Cr Mo Iron — the balance, never listed by a standard — 32.2 % Ni — 42.5 % Cr — 12.5 % Mo — 6 % Traces & impurities · 6.8 % Logarithmic scale, 0.01 % to 100 % — every value here compares directly, decade by decade. | Element | % by weight | |---|---| | C | ≤ 0.1 | | Si | ≤ 0.6 | | Mn | ≤ 2 | | P | 0.02 | | S | 0.01 | | Cr | 11–14 | | Mo | 5–7 — Unusual | | Ni | 40–45 | | Co | ≤ 1 | | Al | ≤ 0.35 | | Ti | 2.35–3.1 — Unusual | | Fe | Balance | Carbon Silicon Manganese Phosphorus Sulfur Chromium Molybdenum Nickel Cobalt Aluminium Titanium Iron 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 | ≤0,10 | — | 0.100 | Max | | Al | ≤0,35 | — | 0.350 | Max | | Si | ≤0,60 | — | 0.600 | Max | | P | 0,02 | 0.020 | 0.020 | Exact | | S | 0,01 | 0.010 | 0.010 | Exact | | Ti | 2,35-3,10 | 2.350 | 3.100 | Range | | Cr | 11,0-14,0 | 11.000 | 14.000 | Range | | Mn | ≤2,00 | — | 2.000 | Max | | Fe | Rest/Bal. | 26.820 | 41.620 | Balance | | Co | ≤1,00 | — | 1.000 | Max | | Ni | 40,0-45,0 | 40.000 | 45.000 | Range | | Mo | 5,00-7,00 | 5.000 | 7.000 | Range | 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 This grade's composition falls outside the published model's validated range (a low-alloy composition window), so no transformation temperature is predicted here. ## 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. ## 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=c0023c59-0217-47ae-bda1-acbfa1bb7b53&designation=0db4ee72-574d-478e-a4f5-63b960200778 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/iso/nw9911.pdf "Datasheet as PDF")