--- title: "1.7147 — Case hardening steels" description: "1.7147 is the material number of the grade also listed as 20MnCr5. Category: Case hardening steels. Designations recorded for this grade: 45." canonical: https://steelequivalents.com/materials/material-no/1.7147 language: en robots: index, follow og_type: website type: material-detail language_alternates: en: https://steelequivalents.com/materials/material-no/1.7147.md cs: https://steelequivalents.com/cs/materiály/číslo-materiálu/1.7147.md de: https://steelequivalents.com/de/werkstoffe/werkstoff-nr/1.7147.md es: https://steelequivalents.com/es/materiales/número-de-material/1.7147.md fr: https://steelequivalents.com/fr/matériaux/numéro-de-matériau/1.7147.md hu: https://steelequivalents.com/hu/anyagok/anyagszám/1.7147.md it: https://steelequivalents.com/it/materiali/numero-materiale/1.7147.md nl: https://steelequivalents.com/nl/materialen/materiaalnummer/1.7147.md pl: https://steelequivalents.com/pl/materiały/numer-materiału/1.7147.md pt: https://steelequivalents.com/pt/materiais/número-do-material/1.7147.md ru: https://steelequivalents.com/ru/материалы/номер-материала/1.7147.md tr: https://steelequivalents.com/tr/malzemeler/malzeme-numarası/1.7147.md zh: https://steelequivalents.com/zh/材料/材料编号/1.7147.md ja: https://steelequivalents.com/ja/材料/材料番号/1.7147.md ar: https://steelequivalents.com/ar/المواد/رقم-المادة/1.7147.md ko: https://steelequivalents.com/ko/재료/재료번호/1.7147.md pt-br: https://steelequivalents.com/pt-br/materiais/número-do-material/1.7147.md hi: https://steelequivalents.com/hi/सामग्री/सामग्री-संख्या/1.7147.md content_hash: sha256:021deda2a3babd5e74ead80c7689539b3483c580b6fc67a8313d79076e00304c 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/1.7147 > Canonical URL: https://steelequivalents.com/materials/material-no/1.7147 > 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 · 45 designations # 1.7147 1.7147 is the material number of the grade also listed as 20MnCr5. It is a material in the category Case hardening steels. We list 45 designations recorded for this grade, in the standards DIN / EN, UNS, AISI / SAE, AFNOR, UNE, ISO, JIS, GB, GOST, UNI, ČSN, STN, PN, COPANT, SRPS and SFS. - ***Material no.* **1.7147**** - [*Category* **Case hardening steels · 60 grades**](/categories/case-hardening-steels "Category: Case hardening steels · 60 grades") - *Designations* **45** [Search](/search "Steel grade search")[Inquiry](/inquiry?material=fec9b76c-6a84-4fdf-a639-890d865a02ee "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/material-no/1.7147.pdf "Datasheet as PDF") ## If you came for one of these The most-used names for this grade. - [DIN / EN 20MnCr5 This grade’s own name](/materials/din-en/20mncr5 "DIN / EN 20MnCr5") - [UNS G51200 This grade’s own name · 7 grades on that route](/materials/uns/g51200 "UNS G51200") - [AISI / SAE 5120 This grade’s own name · 5 grades on that route](/materials/aisi-sae/5120 "AISI / SAE 5120") ## 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 45 designations · 16 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 - [20MnCr5 This grade’s own name](/materials/din-en/20mncr5 "DIN / EN 20MnCr5") - [21MnCr5 Indicative](/materials/din-en/21mncr5 "DIN / EN 21MnCr5") UNS United States · 4 - [G48200 Indicative](/materials/uns/g48200 "UNS G48200") - [G51150 Indicative](/materials/uns/g51150 "UNS G51150") - [G51200 This grade’s own name](/materials/uns/g51200 "UNS G51200") - [H51200 This grade’s own name](/materials/uns/h51200 "UNS H51200") AISI / SAE United States · 4 - [4820 Indicative](/materials/aisi-sae/4820 "AISI / SAE 4820") - [5120 This grade’s own name](/materials/aisi-sae/5120 "AISI / SAE 5120") - [5120H This grade’s own name](/materials/aisi-sae/5120h "AISI / SAE 5120H") - [SAE5120 Indicative](/materials/aisi-sae/sae5120 "AISI / SAE SAE5120") AFNOR France · 2 - [16MC5 Indicative](/materials/afnor/16mc5 "AFNOR 16MC5") - [20MC5 Indicative](/materials/afnor/20mc5 "AFNOR 20MC5") UNE Spain · 1 - [F.150.D Indicative](/materials/une/f-150-d "UNE F.150.D") ISO International · 8 - [16MnCr5 Indicative](/materials/din-en/16mncr5 "ISO 16MnCr5") - [16MnCrS5 Indicative](/materials/din-en/16mncrs5 "ISO 16MnCrS5") - [20Cr4 Indicative](/materials/din-en/20cr4 "ISO 20Cr4") - [20Cr4H Indicative](/materials/iso/20cr4h "ISO 20Cr4H") - [20CrS4 Indicative](/materials/din-en/20crs4 "ISO 20CrS4") - [20MnCr5 Indicative](/materials/din-en/20mncr5 "ISO 20MnCr5") - [20MnCrS5 Indicative](/materials/din-en/20mncrs5 "ISO 20MnCrS5") - [21MnCr5 Indicative](/materials/din-en/21mncr5 "ISO 21MnCr5") JIS Japan · 3 - [SCr420 Indicative](/materials/jis/scr420 "JIS SCr420") - [SCr420H Indicative](/materials/jis/scr420h "JIS SCr420H") - [SMnC420H Indicative](/materials/jis/smnc420h "JIS SMnC420H") GB China · 4 - [20CrH Indicative](/materials/gb/20crh "GB 20CrH") - [20CrMn Indicative](/materials/gb/20crmn "GB 20CrMn") - [20CrMnTi Indicative](/materials/gb/20crmnti "GB 20CrMnTi") - [20MnCr Indicative](/materials/gb/20mncr "GB 20MnCr") GOST Russia / CIS · 6 - [18ChG Indicative](/materials/bds/18chg "GOST 18ChG") - [18ChGT Indicative](/materials/gost/18chgt "GOST 18ChGT") - [18KHG Indicative](/materials/gost/18khg "GOST 18KHG") - [20ChG Indicative](/materials/gost/20chg "GOST 20ChG") - [20X Indicative](/materials/gost/20x "GOST 20X") - [ст.20X Indicative](/materials/gost/st-20x "GOST ст.20X") UNI Italy · 1 - [20MnCr5 Indicative](/materials/din-en/20mncr5 "UNI 20MnCr5") ČSN Czechia · 1 - [14221 Indicative](/materials/csn/14221 "ČSN 14221") STN Slovakia · 1 - [14 221 Indicative](/materials/csn/14221 "STN 14 221") PN Poland · 4 - [16HG Indicative](/materials/pn/16hg "PN 16HG") - [18HGT Indicative](/materials/pn/18hgt "PN 18HGT") - [18HGT 20HG Indicative](/materials/pn/18hgt-20hg "PN 18HGT 20HG") - [20HG Indicative](/materials/pn/20hg "PN 20HG") COPANT Latin America · 2 - [4820 Indicative](/materials/aisi-sae/4820 "COPANT 4820") - [5120 Indicative](/materials/aisi-sae/5120 "COPANT 5120") SRPS Serbia · 1 - [Č.4321 Indicative](/materials/srps/c-4321 "SRPS Č.4321") SFS Finland · 1 - [510 Indicative](/materials/bs/510 "SFS 510") Every designation on file is listed — no truncation, no “+ n more”. Each one is itself a route that leads back here. ## Chemical composition 6 elements on file · weight % What this alloy is Fe Mn Cr Si Iron — the balance, never listed by a standard — 96.9 % Mn — 1.3 % Cr — 1.2 % Si — 0.4 % Traces & impurities · 0.3 % Logarithmic scale, 0.01 % to 100 % — every value here compares directly, decade by decade. | Element | % by weight | |---|---| | C | 0.17–0.22 | | Si | ≤ 0.4 | | Mn | 1.1–1.4 | | P | 0.025 | | S | 0.035 | | Cr | 1–1.3 | Carbon Silicon Manganese Phosphorus Sulfur Chromium 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 | 0,17-0,22 | 0.170 | 0.220 | Range | | Si | ≤0,40 | — | 0.400 | Max | | P | 0,025 | 0.025 | 0.025 | Exact | | S | 0,035 | 0.035 | 0.035 | Exact | | Cr | 1,00-1,30 | 1.000 | 1.300 | Range | | Mn | 1,10-1,40 | 1.100 | 1.400 | 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, Mo. ## Physical & mechanical properties Density 7,75 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 5 conditions · 5 values By delivery state**Treated to improve shearability** source `steelnumber` | Delivery state | HB | |---|---| | Treated to improve shearability | 255 | By delivery state**Soft annealed** source `steelnumber` | Delivery state | HB | |---|---| | Soft annealed | 217 | By delivery state**Treated to hardness range** source `steelnumber` | Delivery state | HB | |---|---| | Treated to hardness range | 170 – 217 | By delivery state**Treated to ferrite-pearlite structure and hardness range** source `steelnumber` | Delivery state | HB | |---|---| | Treated to ferrite-pearlite structure and hardness range | 152 – 201 | By delivery state**Normalized** source `steelnumber` | Delivery state | HB | |---|---| | Normalized | 140 – 201 | 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 1.7, a shared category, and a published range for Mn / 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. [20MnCrS5 1.7149 Mn 1,10-1,40 · Cr 1,00-1,30 - ΔMn 0.00 - ΔCr 0.00 - 17 designations](/materials/din-en/20mncrs5 "20MnCrS5")[1.7131 1.7131 Mn 1,00-1,30 · Cr 0,80-1,10 - ΔMn 0.10 - ΔCr 0.20 - 78 designations](/materials/material-no/1.7131 "1.7131")[16MnCrS5 1.7139 Mn 1,00-1,30 · Cr 0,80-1,10 - ΔMn 0.10 - ΔCr 0.20 - 20 designations](/materials/din-en/16mncrs5 "16MnCrS5")[16MnCrB5 1.7160 Mn 1,00-1,30 · Cr 0,80-1,10 - ΔMn 0.10 - ΔCr 0.20 - 1 designations](/materials/din-en/16mncrb5 "16MnCrB5")[1.7262 1.7262 Mn 0,80-1,10 · Cr 1,00-1,30 - ΔMn 0.30 - ΔCr 0.00 - 63 designations](/materials/material-no/1.7262 "1.7262")[20CrMo5 1.7264 Mn 0,90-1,20 · Cr 1,10-1,40 - ΔMn 0.20 - ΔCr 0.10 - 6 designations](/materials/din-en/20crmo5 "20CrMo5") ## 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=fec9b76c-6a84-4fdf-a639-890d865a02ee "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/material-no/1.7147.pdf "Datasheet as PDF")