--- title: "ЭИ268 — Special steels for aviation and aerospace" description: "ЭИ268 in GOST: material number 1.4044, also listed as X15CrNi17-3. It is a material in the category Special steels for aviation and aerospace." canonical: https://steelequivalents.com/materials/gost/ei268 language: en robots: index, follow og_type: website type: material-detail language_alternates: en: https://steelequivalents.com/materials/gost/ei268.md cs: https://steelequivalents.com/cs/materiály/gost/ei268.md de: https://steelequivalents.com/de/werkstoffe/gost/ei268.md es: https://steelequivalents.com/es/materiales/gost/ei268.md fr: https://steelequivalents.com/fr/matériaux/gost/ei268.md hu: https://steelequivalents.com/hu/anyagok/gost/ei268.md it: https://steelequivalents.com/it/materiali/gost/ei268.md nl: https://steelequivalents.com/nl/materialen/gost/ei268.md pl: https://steelequivalents.com/pl/materiały/gost/ei268.md pt: https://steelequivalents.com/pt/materiais/gost/ei268.md ru: https://steelequivalents.com/ru/материалы/gost/эи268.md tr: https://steelequivalents.com/tr/malzemeler/gost/ei268.md zh: https://steelequivalents.com/zh/材料/gost/ei268.md ja: https://steelequivalents.com/ja/材料/gost/ei268.md ar: https://steelequivalents.com/ar/المواد/gost/ei268.md ko: https://steelequivalents.com/ko/재료/gost/ei268.md pt-br: https://steelequivalents.com/pt-br/materiais/gost/ei268.md hi: https://steelequivalents.com/hi/सामग्री/gost/ei268.md content_hash: sha256:f083692124f0b91e92be079d57e957a9815f0d3c4b8d47b67b86f7fbf0b5905d generated: 2026-09-22 --- > **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/gost/ei268 > Canonical URL: https://steelequivalents.com/materials/gost/ei268 > 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. GOST · Russia / CIS · 33 designations # ЭИ268 ЭИ268 is a designation in GOST for the material held under material number 1.4044, also listed as X15CrNi17-3. It is a material in the category Special steels for aviation and aerospace. We list 33 designations recorded for this grade, in the standards DIN / EN, UNS, AISI / SAE, ASTM, BS, AFNOR, SAE AMS, JIS and GOST. - [*Material no.* **1.4044**](/materials/material-no/1.4044 "Material no.: 1.4044") - [*Category* **Special steels for aviation and aerospace · 39 grades**](/categories/special-steels-for-aviation-and-aerospace "Category: Special steels for aviation and aerospace · 39 grades") - *Designations* **33** [Search](/search "Steel grade search")[Inquiry](/inquiry?material=010dd31a-2240-4ab1-ba79-0f11dda455c1&designation=3b4baa76-d02e-4de5-80b8-5e5c23a288f9 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/gost/ei268.pdf "Datasheet as PDF") ## If you came for one of these The most-used names for this grade. - [DIN / EN X15CrNi17-3 This grade’s own name](/materials/din-en/x15crni17-3 "DIN / EN X15CrNi17-3") - [UNS S43100 This grade’s own name · 2 grades on that route](/materials/uns/s43100 "UNS S43100") - [AISI / SAE 431 This grade’s own name · 2 grades on that route](/materials/aisi-sae/431 "AISI / SAE 431") ## About Special steels for aviation and aerospace Special steels for aviation and aerospace are engineered steels designed to provide controlled mechanical properties and reliable performance in demanding service. Their alloying and heat-treatment capabilities support components that require a combination of strength, toughness and fatigue resistance, including aircraft structures and engine parts. This describes the material class as a whole. Always confirm the individual grade against the standard before ordering. ## Also known as 33 designations · 9 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 - [X15CrNi17-3 This grade’s own name](/materials/din-en/x15crni17-3 "DIN / EN X15CrNi17-3") UNS United States · 1 - [S43100 This grade’s own name](/materials/uns/s43100 "UNS S43100") AISI / SAE United States · 2 - [431 This grade’s own name](/materials/aisi-sae/431 "AISI / SAE 431") - [51431 Indicative](/materials/aisi-sae/51431 "AISI / SAE 51431") ASTM United States · 16 - [A176 Indicative](/materials/astm/a176 "ASTM A176") - [A276 Indicative](/materials/astm/a276 "ASTM A276") - [A314 Indicative](/materials/astm/a314 "ASTM A314") - [A473 Indicative](/materials/astm/a473 "ASTM A473") - [A478 Indicative](/materials/astm/a478 "ASTM A478") - [A479 Indicative](/materials/astm/a479 "ASTM A479") - [A484 Indicative](/materials/astm/a484 "ASTM A484") - [A493 Indicative](/materials/astm/a493 "ASTM A493") - [A580 Indicative](/materials/astm/a580 "ASTM A580") - [A593 Indicative](/materials/astm/a593 "ASTM A593") - [A594 Indicative](/materials/astm/a594 "ASTM A594") - [F1613 Indicative](/materials/astm/f1613 "ASTM F1613") - [F2281 Indicative](/materials/astm/f2281 "ASTM F2281") - [F738 Indicative](/materials/astm/f738 "ASTM F738") - [F836 Indicative](/materials/astm/f836 "ASTM F836") - [F899 Indicative](/materials/astm/f899 "ASTM F899") BS United Kingdom · 3 - [431S29 Indicative](/materials/bs/431s29 "BS 431S29") - [7S80 Indicative](/materials/bs/7s80 "BS 7S80") - [S80 Indicative](/materials/bs/s80 "BS S80") AFNOR France · 1 - [Z15CN16-02 Indicative](/materials/afnor/z15cn16-02 "AFNOR Z15CN16-02") SAE AMS United States / Aerospace · 2 - [5628 Indicative bar forging wire](/materials/ams/5628 "SAE AMS 5628") - [5682 Indicative](/materials/ams/5682 "SAE AMS 5682") JIS Japan · 1 - [SUS431 Indicative](/materials/jis/sus431 "JIS SUS431") GOST Russia / CIS · 6 - [14KH17N2 Indicative](/materials/gost/14kh17n2 "GOST 14KH17N2") - [14Kh17N2L Indicative](/materials/gost/14kh17n2l "GOST 14Kh17N2L") - [14Х17Н2 Indicative](/materials/gost/14kh17n2 "GOST 14Х17Н2") - [1Х17Н2 Indicative](/materials/gost/1kh17n2 "GOST 1Х17Н2") - **ЭИ268 Indicative** - [ЭИ268Л Indicative](/materials/gost/ei268l "GOST ЭИ268Л") Every designation on file is listed — no truncation, no “+ n more”. Each one is itself a route that leads back here. ## Chemical composition 7 elements on file · weight % What this alloy is Fe Cr Ni Si Iron — the balance, never listed by a standard — 78.8 % Cr — 16.5 % Ni — 2.5 % Si — 1 % Traces & impurities · 1.2 % Logarithmic scale, 0.01 % to 100 % — every value here compares directly, decade by decade. | Element | % by weight | |---|---| | C | 0.12–0.2 | | Si | ≤ 1 | | Mn | ≤ 1 | | P | 0.035 | | S | 0.025 | | Cr | 15–18 | | Ni | 2–3 | Carbon Silicon Manganese Phosphorus Sulfur Chromium Nickel 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 | 0,12-0,20 | 0.120 | 0.200 | Range | | Si | ≤1,00 | — | 1.000 | Max | | P | 0,035 | 0.035 | 0.035 | Exact | | S | 0,025 | 0.025 | 0.025 | Exact | | Cr | 15,0-18,0 | 15.000 | 18.000 | Range | | Mn | ≤1,00 | — | 1.000 | Max | | Ni | 2,00-3,00 | 2.000 | 3.000 | 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 Not enough recorded composition to predict a transformation temperature for this grade — missing: Mo. ## 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 2 conditions · 10 values By heat-treated condition**no delivery state stated** source `splav` | Heat-treated condition | Rm N/mm² | Re N/mm² | A5% | Z% | KCU kJ/m² | |---|---|---|---|---|---| | Casting | 950 | 750 | 8 | 20 | 250 | By heat-treated condition**no delivery state stated** source `splav` | Heat-treated condition | Rm N/mm² | Re N/mm² | A5% | Z% | KCU kJ/m² | |---|---|---|---|---|---| | Casting | 850 | 650 | 8 | 20 | 350 | 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 1.4, a shared category, and a published range for Cr / 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. [X5CrNiCuNb17-4-4 1.4548 Cr 15,0-17,5 · Ni 3,00-5,00 - ΔCr 0.25 - ΔNi 1.50 - 21 designations](/materials/din-en/x5crnicunb17-4-4 "X5CrNiCuNb17-4-4")[X5CrNiCu15-5 1.4545 Cr 15,0-15,5 · Ni 3,00-5,50 - ΔCr 1.25 - ΔNi 1.75 - 12 designations](/materials/din-en/x5crnicu15-5 "X5CrNiCu15-5") ## 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=010dd31a-2240-4ab1-ba79-0f11dda455c1&designation=3b4baa76-d02e-4de5-80b8-5e5c23a288f9 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/gost/ei268.pdf "Datasheet as PDF")