--- title: "1.7271 — Case hardening steels" description: "1.7271 is the material number of the grade also listed as 23CrMoB3-3. Category: Case hardening steels. Designations recorded for this grade: 1." canonical: https://steelequivalents.com/materials/material-no/1.7271 language: en robots: index, follow og_type: website type: material-detail language_alternates: en: https://steelequivalents.com/materials/material-no/1.7271.md cs: https://steelequivalents.com/cs/materiály/číslo-materiálu/1.7271.md de: https://steelequivalents.com/de/werkstoffe/werkstoff-nr/1.7271.md es: https://steelequivalents.com/es/materiales/número-de-material/1.7271.md fr: https://steelequivalents.com/fr/matériaux/numéro-de-matériau/1.7271.md hu: https://steelequivalents.com/hu/anyagok/anyagszám/1.7271.md it: https://steelequivalents.com/it/materiali/numero-materiale/1.7271.md nl: https://steelequivalents.com/nl/materialen/materiaalnummer/1.7271.md pl: https://steelequivalents.com/pl/materiały/numer-materiału/1.7271.md pt: https://steelequivalents.com/pt/materiais/número-do-material/1.7271.md ru: https://steelequivalents.com/ru/материалы/номер-материала/1.7271.md tr: https://steelequivalents.com/tr/malzemeler/malzeme-numarası/1.7271.md zh: https://steelequivalents.com/zh/材料/材料编号/1.7271.md ja: https://steelequivalents.com/ja/材料/材料番号/1.7271.md ar: https://steelequivalents.com/ar/المواد/رقم-المادة/1.7271.md ko: https://steelequivalents.com/ko/재료/재료번호/1.7271.md pt-br: https://steelequivalents.com/pt-br/materiais/número-do-material/1.7271.md hi: https://steelequivalents.com/hi/सामग्री/सामग्री-संख्या/1.7271.md content_hash: sha256:ce1efbf47a22534779a607381b9cd39d7ade31922bc5ca63425530a704ffc5b5 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/1.7271 > Canonical URL: https://steelequivalents.com/materials/material-no/1.7271 > 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 · 1 designation # 1.7271 1.7271 is the material number of the grade also listed as 23CrMoB3-3. It is a material in the category Case hardening steels. We list 1 designations recorded for this grade, in the standards DIN / EN. - ***Material no.* **1.7271**** - [*Category* **Case hardening steels · 60 grades**](/categories/case-hardening-steels "Category: Case hardening steels · 60 grades") - *Designations* **1** [Search](/search "Steel grade search")[Inquiry](/inquiry?material=66dbb346-ecbc-4e7d-a07b-ad4b4bc67afc "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/material-no/1.7271.pdf "Datasheet as PDF") ## If you came for one of these The most-used names for this grade. - [DIN / EN 23CrMoB3-3 This grade’s own name](/materials/din-en/23crmob3-3 "DIN / EN 23CrMoB3-3") ## About Case hardening steels Case hardening steels are steels designed to develop a hard, wear-resistant surface while retaining a tough and ductile core. They are used for components such as gears, shafts and other machine parts exposed to contact wear and cyclic loading. This describes the material class as a whole. Always confirm the individual grade against the standard before ordering. ## Also known as 1 designations · 1 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 - [23CrMoB3-3 This grade’s own name](/materials/din-en/23crmob3-3 "DIN / EN 23CrMoB3-3") 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 Cr Mo Iron — the balance, never listed by a standard — 97.5 % Mn — 0.8 % Cr — 0.8 % Mo — 0.4 % Traces & impurities · 0.5 % Logarithmic scale, 0.01 % to 100 % — every value here compares directly, decade by decade. | Element | % by weight | |---|---| | C | 0.2–0.25 | | Si | 0.15–0.35 | | Mn | 0.7–0.9 | | P | 0.035 | | S | 0.035 | | Cr | 0.7–0.9 | | Mo | 0.3–0.4 | | B | 0.0008–0.005 | Carbon Silicon Manganese Phosphorus Sulfur Chromium Molybdenum Boron 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 | |---|---|---|---|---| | B | 0,0008-0,0050 | 0.001 | 0.005 | Range | | C | 0,20-0,25 | 0.200 | 0.250 | Range | | Si | 0,15-0,35 | 0.150 | 0.350 | Range | | P | 0,035 | 0.035 | 0.035 | Exact | | S | 0,035 | 0.035 | 0.035 | Exact | | Cr | 0,70-0,90 | 0.700 | 0.900 | Range | | Mn | 0,70-0,90 | 0.700 | 0.900 | Range | | Mo | 0,30-0,40 | 0.300 | 0.400 | 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. ## 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 1.7, a shared category, and a published range for Cr / Mn 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. [22CrMoS3-5 1.7333 Cr 0,70-1,00 · Mn 0,70-1,00 - ΔCr 0.05 - ΔMn 0.05 - 1 designations](/materials/din-en/22crmos3-5 "22CrMoS3-5")[17CrS3 1.7014 Cr 0,70-1,00 · Mn 0,60-0,90 - ΔCr 0.05 - ΔMn 0.05 - 2 designations](/materials/din-en/17crs3 "17CrS3")[17Cr3 1.7016 Cr 0,70-1,00 · Mn 0,60-0,90 - ΔCr 0.05 - ΔMn 0.05 - 36 designations](/materials/din-en/17cr3 "17Cr3")[22CrV3 1.7511 Cr 0,65-0,80 · Mn 0,60-0,75 - ΔCr 0.07 - ΔMn 0.13 - 5 designations](/materials/din-en/22crv3 "22CrV3")[20Cr4 1.7027 Cr 0,90-1,20 · Mn 0,60-0,90 - ΔCr 0.25 - ΔMn 0.05 - 25 designations](/materials/din-en/20cr4 "20Cr4")[20CrS4 1.7028 Cr 0,90-1,20 · Mn 0,60-0,90 - ΔCr 0.25 - ΔMn 0.05 - 1 designations](/materials/din-en/20crs4 "20CrS4") ## 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=66dbb346-ecbc-4e7d-a07b-ad4b4bc67afc "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/material-no/1.7271.pdf "Datasheet as PDF")