--- title: "1.6543 — Case hardening steels" description: "1.6543 is the material number of the grade also listed as 21 NiCrMo 2 2. Category: Case hardening steels. Designations recorded for this grade: 18." canonical: https://steelequivalents.com/materials/material-no/1.6543 language: en robots: index, follow og_type: website type: material-detail language_alternates: en: https://steelequivalents.com/materials/material-no/1.6543.md cs: https://steelequivalents.com/cs/materiály/číslo-materiálu/1.6543.md de: https://steelequivalents.com/de/werkstoffe/werkstoff-nr/1.6543.md es: https://steelequivalents.com/es/materiales/número-de-material/1.6543.md fr: https://steelequivalents.com/fr/matériaux/numéro-de-matériau/1.6543.md hu: https://steelequivalents.com/hu/anyagok/anyagszám/1.6543.md it: https://steelequivalents.com/it/materiali/numero-materiale/1.6543.md nl: https://steelequivalents.com/nl/materialen/materiaalnummer/1.6543.md pl: https://steelequivalents.com/pl/materiały/numer-materiału/1.6543.md pt: https://steelequivalents.com/pt/materiais/número-do-material/1.6543.md ru: https://steelequivalents.com/ru/материалы/номер-материала/1.6543.md tr: https://steelequivalents.com/tr/malzemeler/malzeme-numarası/1.6543.md zh: https://steelequivalents.com/zh/材料/材料编号/1.6543.md ja: https://steelequivalents.com/ja/材料/材料番号/1.6543.md ar: https://steelequivalents.com/ar/المواد/رقم-المادة/1.6543.md ko: https://steelequivalents.com/ko/재료/재료번호/1.6543.md pt-br: https://steelequivalents.com/pt-br/materiais/número-do-material/1.6543.md hi: https://steelequivalents.com/hi/सामग्री/सामग्री-संख्या/1.6543.md content_hash: sha256:9635b08a63cf2e53948ffa0fe955547d3ba43c337a21f9ea9707d2cd9452e9f3 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/1.6543 > Canonical URL: https://steelequivalents.com/materials/material-no/1.6543 > 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 · 18 designations # 1.6543 1.6543 is the material number of the grade also listed as 21 NiCrMo 2 2. It is a material in the category Case hardening steels. We list 18 designations recorded for this grade, in the standards DIN / EN, UNS, AISI / SAE and PN. - ***Material no.* **1.6543**** - [*Category* **Case hardening steels · 60 grades**](/categories/case-hardening-steels "Category: Case hardening steels · 60 grades") - *Designations* **18** [Search](/search "Steel grade search")[Inquiry](/inquiry?material=3c87548e-6ed2-4277-a1c8-fa09d0bf44aa "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/material-no/1.6543.pdf "Datasheet as PDF") ## If you came for one of these The most-used names for this grade. - [UNS G86220 This grade’s own name](/materials/uns/g86220 "UNS G86220") - [AISI / SAE 8622 This grade’s own name](/materials/aisi-sae/8622 "AISI / SAE 8622") ## 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 18 designations · 4 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 - [21 NiCrMo 2 2 This grade’s own name Withdrawn](/materials/din-en/21-nicrmo-2-2 "DIN / EN 21 NiCrMo 2 2") UNS United States · 6 - [G86220 This grade’s own name](/materials/uns/g86220 "UNS G86220") - [G87200 This grade’s own name](/materials/uns/g87200 "UNS G87200") - [G88200 This grade’s own name](/materials/uns/g88200 "UNS G88200") - [H86220 This grade’s own name](/materials/uns/h86220 "UNS H86220") - [H87200 This grade’s own name](/materials/uns/h87200 "UNS H87200") - [H88200 This grade’s own name](/materials/uns/h88200 "UNS H88200") AISI / SAE United States · 10 - [8622 This grade’s own name](/materials/aisi-sae/8622 "AISI / SAE 8622") - [8622H This grade’s own name](/materials/aisi-sae/8622h "AISI / SAE 8622H") - [8622RH This grade’s own name](/materials/aisi-sae/8622rh "AISI / SAE 8622RH") - [8719 This grade’s own name](/materials/aisi-sae/8719 "AISI / SAE 8719") - [8720 This grade’s own name](/materials/aisi-sae/8720 "AISI / SAE 8720") - [8720H This grade’s own name](/materials/aisi-sae/8720h "AISI / SAE 8720H") - [8720RH This grade’s own name](/materials/aisi-sae/8720rh "AISI / SAE 8720RH") - [8822 This grade’s own name](/materials/aisi-sae/8822 "AISI / SAE 8822") - [8822H This grade’s own name](/materials/aisi-sae/8822h "AISI / SAE 8822H") - [8822RH This grade’s own name](/materials/aisi-sae/8822rh "AISI / SAE 8822RH") PN Poland · 1 - [22HNM Indicative](/materials/pn/22hnm "PN 22HNM") 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 Ni Cr Iron — the balance, never listed by a standard — 97.4 % Mn — 0.8 % Ni — 0.6 % Cr — 0.5 % Traces & impurities · 0.8 % Logarithmic scale, 0.01 % to 100 % — every value here compares directly, decade by decade. | Element | % by weight | |---|---| | C | 0.18–0.23 | | Si | 0.2–0.35 | | Mn | 0.7–0.9 | | P | 0.035 | | S | 0.035 | | Cr | 0.4–0.6 | | Mo | 0.2–0.3 | | Ni | 0.4–0.7 | Carbon Silicon Manganese Phosphorus Sulfur Chromium Molybdenum 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 | 0,18-0,23 | 0.180 | 0.230 | Range | | Si | 0,20-0,35 | 0.200 | 0.350 | Range | | P | 0,035 | 0.035 | 0.035 | Exact | | S | 0,035 | 0.035 | 0.035 | Exact | | Cr | 0,40-0,60 | 0.400 | 0.600 | Range | | Mn | 0,70-0,90 | 0.700 | 0.900 | Range | | Ni | 0,40-0,70 | 0.400 | 0.700 | Range | | Mo | 0,20-0,30 | 0.200 | 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 computed from composition · °C Predicted Ae3 803 °C Predicted Ae1 722 °C Predicted Acm 466 °C Predicted Bs 549 °C These four temperatures are a CALCULATION from this grade's own composition, using the published Li, Niebuhr, Meekisho & Atteridge (1998) model — never a measurement, and computed from the UPPER BOUND of each element's specified range, not a mid-range figure. Where this grade also has a measured transformation point (Ac1, Ac3, Ar1, Ar3) on file, it is shown separately, in Physical & mechanical properties, and is never replaced by the predicted figures here — Ae (predicted, equilibrium) and Ac/Ar (measured, on heating or cooling) are different physical quantities and can differ by tens of degrees; a mismatch between the two is not an error in either. ## 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 1.6, a shared category, and a published range for Mn / 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. [1.6523 1.6523 Mn 0,65-0,95 · Ni 0,40-0,70 - ΔMn 0.00 - ΔNi 0.00 - 63 designations](/materials/material-no/1.6523 "1.6523")[20NiCrMoS2-2 1.6526 Mn 0,65-0,95 · Ni 0,40-0,70 - ΔMn 0.00 - ΔNi 0.00 - 19 designations](/materials/din-en/20nicrmos2-2 "20NiCrMoS2-2")[20MnNiCrMo3-2 1.6522 Mn 0,70-1,00 · Ni 0,40-0,70 - ΔMn 0.05 - ΔNi 0.00 - 14 designations](/materials/din-en/20mnnicrmo3-2 "20MnNiCrMo3-2")[20NiCrMo3 1.6527 Mn 0,70-1,00 · Ni 0,70-0,90 - ΔMn 0.05 - ΔNi 0.25 - 1 designations](/materials/din-en/20nicrmo3 "20NiCrMo3") ## 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=3c87548e-6ed2-4277-a1c8-fa09d0bf44aa "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/material-no/1.6543.pdf "Datasheet as PDF")