--- title: "6278 — M50NiL, 4 equivalent designations" description: "6278 in SAE AMS: material number 1.3590, also listed as M50NiL. It is a material in the category Others. Designations recorded for this grade: 4." canonical: https://steelequivalents.com/materials/ams/6278 language: en robots: index, follow og_type: website type: material-detail language_alternates: en: https://steelequivalents.com/materials/ams/6278.md cs: https://steelequivalents.com/cs/materiály/ams/6278.md de: https://steelequivalents.com/de/werkstoffe/ams/6278.md es: https://steelequivalents.com/es/materiales/ams/6278.md fr: https://steelequivalents.com/fr/matériaux/ams/6278.md hu: https://steelequivalents.com/hu/anyagok/ams/6278.md it: https://steelequivalents.com/it/materiali/ams/6278.md nl: https://steelequivalents.com/nl/materialen/ams/6278.md pl: https://steelequivalents.com/pl/materiały/ams/6278.md pt: https://steelequivalents.com/pt/materiais/ams/6278.md ru: https://steelequivalents.com/ru/материалы/ams/6278.md tr: https://steelequivalents.com/tr/malzemeler/ams/6278.md zh: https://steelequivalents.com/zh/材料/ams/6278.md ja: https://steelequivalents.com/ja/材料/ams/6278.md ar: https://steelequivalents.com/ar/المواد/ams/6278.md ko: https://steelequivalents.com/ko/재료/ams/6278.md pt-br: https://steelequivalents.com/pt-br/materiais/ams/6278.md hi: https://steelequivalents.com/hi/सामग्री/ams/6278.md content_hash: sha256:8b12a95c08d3e3107dc0087874ae5946a85fe526b37585ffdfc771bbce069c86 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/ams/6278 > Canonical URL: https://steelequivalents.com/materials/ams/6278 > 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. SAE AMS · United States / Aerospace · 4 designations # 6278 6278 is a designation in SAE AMS for the material held under material number 1.3590, also listed as M50NiL. It is a material in the category Others. We list 4 designations recorded for this grade, in the standards DIN / EN, UNS and SAE AMS. - [*Material no.* **1.3590**](/materials/material-no/1.3590 "Material no.: 1.3590") - [*Category* **Others · 1754 grades**](/categories/others "Category: Others · 1754 grades") - *Designations* **4** [Search](/search "Steel grade search")[Inquiry](/inquiry?material=951acbe7-2381-4358-a281-16b20b002fd2&designation=1fdb7bd5-723e-43ba-ac3b-fe1405f65974 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/ams/6278.pdf "Datasheet as PDF") ## If you came for one of these The most-used names for this grade. - [UNS K91231 This grade’s own name](/materials/uns/k91231 "UNS K91231") ## About Others These are miscellaneous metallic alloys that do not fit a more specific material family and may be based on iron, nickel, cobalt, copper or other alloy systems. They are selected for applications requiring particular combinations of strength, hardness, toughness, wear resistance or resistance to demanding service conditions. This describes the material class as a whole. Always confirm the individual grade against the standard before ordering. ## Also known as 4 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 · 2 - [13MoCrNiV42-16-14 Indicative](/materials/din-en/13mocrniv42-16-14 "DIN / EN 13MoCrNiV42-16-14") - [M50NiL This grade’s own name Withdrawn](/materials/din-en/m50nil "DIN / EN M50NiL") UNS United States · 1 - [K91231 This grade’s own name](/materials/uns/k91231 "UNS K91231") SAE AMS United States / Aerospace · 1 - **6278 Indicative** Every designation on file is listed — no truncation, no “+ n more”. Each one is itself a route that leads back here. ## Chemical composition 5 elements on file · weight % What this alloy is Fe Mo Cr Ni Iron — the balance, never listed by a standard — 87 % Mo — 4.2 % Cr — 4.1 % Ni — 3.4 % Traces & impurities · 1.3 % Logarithmic scale, 0.01 % to 100 % — every value here compares directly, decade by decade. | Element | % by weight | |---|---| | C | ≈ 0.12 | | Cr | ≈ 4.1 | | Mo | ≈ 4.2 | | Ni | ≈ 3.4 | | V | ≈ 1.2 | Carbon Chromium Molybdenum Nickel Vanadium 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 | 0.120 | 0.120 | Indicative | | V | ~1,20 | 1.200 | 1.200 | Indicative | | Cr | ~4,10 | 4.100 | 4.100 | Indicative | | Ni | ~3,40 | 3.400 | 3.400 | Indicative | | Mo | ~4,20 | 4.200 | 4.200 | Indicative | 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: Mn, Si. ## 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. ## Similar grades — and why Selection rule, stated so you can disagree with it: same number class 1.3, a shared category, and a published range for Mo / Cr 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. [13MoCrNi42-16-14 1.3555 Mo 4,00-4,50 · Cr 3,90-4,30 - ΔMo 0.05 - ΔCr 0.00 - 1 designations](/materials/din-en/13mocrni42-16-14 "13MoCrNi42-16-14") ## 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=951acbe7-2381-4358-a281-16b20b002fd2&designation=1fdb7bd5-723e-43ba-ac3b-fe1405f65974 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/ams/6278.pdf "Datasheet as PDF")