--- title: "K12542 — Heat-resistant structural steels" description: "K12542 in UNS: material number 1.8812, also listed as 18MnMoV5-2. Category: Heat-resistant structural steels. Designations recorded for this grade: 7." canonical: https://steelequivalents.com/materials/uns/k12542 language: en robots: index, follow og_type: website type: material-detail language_alternates: en: https://steelequivalents.com/materials/uns/k12542.md cs: https://steelequivalents.com/cs/materiály/uns/k12542.md de: https://steelequivalents.com/de/werkstoffe/uns/k12542.md es: https://steelequivalents.com/es/materiales/uns/k12542.md fr: https://steelequivalents.com/fr/matériaux/uns/k12542.md hu: https://steelequivalents.com/hu/anyagok/uns/k12542.md it: https://steelequivalents.com/it/materiali/uns/k12542.md nl: https://steelequivalents.com/nl/materialen/uns/k12542.md pl: https://steelequivalents.com/pl/materiały/uns/k12542.md pt: https://steelequivalents.com/pt/materiais/uns/k12542.md ru: https://steelequivalents.com/ru/материалы/uns/k12542.md tr: https://steelequivalents.com/tr/malzemeler/uns/k12542.md zh: https://steelequivalents.com/zh/材料/uns/k12542.md ja: https://steelequivalents.com/ja/材料/uns/k12542.md ar: https://steelequivalents.com/ar/المواد/uns/k12542.md ko: https://steelequivalents.com/ko/재료/uns/k12542.md pt-br: https://steelequivalents.com/pt-br/materiais/uns/k12542.md hi: https://steelequivalents.com/hi/सामग्री/uns/k12542.md content_hash: sha256:1e29c7bb87c0803c881c1b40f00e3162184238323e4a956fa4fa7de410777139 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/uns/k12542 > Canonical URL: https://steelequivalents.com/materials/uns/k12542 > 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. UNS · United States · 7 designations # K12542 K12542 is a designation in UNS for the material held under material number 1.8812, also listed as 18MnMoV5-2. It is a material in the category Heat-resistant structural steels. We list 7 designations recorded for this grade, in the standards DIN / EN and UNS. - [*Material no.* **1.8812**](/materials/material-no/1.8812 "Material no.: 1.8812") - [*Category* **Heat-resistant structural steels · 62 grades**](/categories/heat-resistant-structural-steels "Category: Heat-resistant structural steels · 62 grades") - *Designations* **7** [Search](/search "Steel grade search")[Inquiry](/inquiry?material=21253d85-da2c-41f0-96ab-5603aa0b5cd7&designation=410f9987-acd1-4c8b-8641-e2e69b778852 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/uns/k12542.pdf "Datasheet as PDF") ## If you came for one of these The most-used names for this grade. - [DIN / EN 18MnMoV5-2 This grade’s own name](/materials/din-en/18mnmov5-2 "DIN / EN 18MnMoV5-2") - [UNS K11742 This grade’s own name](/materials/uns/k11742 "UNS K11742") ## About Heat-resistant structural steels Heat-resistant structural steels are structural steels designed to retain useful strength and dimensional stability at elevated temperatures. They are used for load-bearing components in hot-service equipment where mechanical performance must be maintained during heating. This describes the material class as a whole. Always confirm the individual grade against the standard before ordering. ## Also known as 7 designations · 2 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 - [18MnMoV5-2 This grade’s own name](/materials/din-en/18mnmov5-2 "DIN / EN 18MnMoV5-2") UNS United States · 6 - [K11742 This grade’s own name](/materials/uns/k11742 "UNS K11742") - [K11803 This grade’s own name](/materials/uns/k11803 "UNS K11803") - [K12003 This grade’s own name](/materials/uns/k12003 "UNS K12003") - [K12021 This grade’s own name](/materials/uns/k12021 "UNS K12021") - [K12022 This grade’s own name](/materials/uns/k12022 "UNS K12022") - **K12542 This grade’s own name** Every designation on file is listed — no truncation, no “+ n more”. Each one is itself a route that leads back here. ## Chemical composition 8 elements on file · weight % What this alloy is Fe Mn Si C Iron — the balance, never listed by a standard — 97.9 % Mn — 1.3 % Si — 0.4 % C — 0.2 % Traces & impurities · 0.4 % Logarithmic scale, 0.01 % to 100 % — every value here compares directly, decade by decade. | Element | % by weight | |---|---| | C | ≤ 0.2 | | Si | 0.2–0.5 | | Mn | 1–1.5 | | P | 0.03 | | S | 0.025 | | Mo | 0.1–0.3 | | V | 0.05–0.1 | | N | 0.02 | Carbon Silicon Manganese Phosphorus Sulfur Molybdenum Vanadium Nitrogen 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 | ≤0,20 | — | 0.200 | Max | | N | 0,02 | 0.020 | 0.020 | Exact | | Si | 0,20-0,50 | 0.200 | 0.500 | Range | | P | 0,03 | 0.030 | 0.030 | Exact | | S | 0,025 | 0.025 | 0.025 | Exact | | V | 0,05-0,10 | 0.050 | 0.100 | Range | | Mn | 1,00-1,50 | 1.000 | 1.500 | Range | | Mo | 0,10-0,30 | 0.100 | 0.300 | 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: Ni, Cr. ## 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=21253d85-da2c-41f0-96ab-5603aa0b5cd7&designation=410f9987-acd1-4c8b-8641-e2e69b778852 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/uns/k12542.pdf "Datasheet as PDF")