--- title: "C40E — Quenched and tempered steels" description: "C40E: 25 equivalent designations across 17 standards, with the recorded chemical composition shown next to the source text." canonical: https://steelequivalents.com/materials/din-en/c40e language: en robots: index, follow og_type: website type: material-detail language_alternates: en: https://steelequivalents.com/materials/din-en/c40e.md cs: https://steelequivalents.com/cs/materiály/din-en/c40e.md de: https://steelequivalents.com/de/werkstoffe/din-en/c40e.md es: https://steelequivalents.com/es/materiales/din-en/c40e.md fr: https://steelequivalents.com/fr/matériaux/din-en/c40e.md hu: https://steelequivalents.com/hu/anyagok/din-en/c40e.md it: https://steelequivalents.com/it/materiali/din-en/c40e.md nl: https://steelequivalents.com/nl/materialen/din-en/c40e.md pl: https://steelequivalents.com/pl/materiały/din-en/c40e.md pt: https://steelequivalents.com/pt/materiais/din-en/c40e.md ru: https://steelequivalents.com/ru/материалы/din-en/c40e.md tr: https://steelequivalents.com/tr/malzemeler/din-en/c40e.md zh: https://steelequivalents.com/zh/材料/din-en/c40e.md ja: https://steelequivalents.com/ja/材料/din-en/c40e.md ar: https://steelequivalents.com/ar/المواد/din-en/c40e.md ko: https://steelequivalents.com/ko/재료/din-en/c40e.md pt-br: https://steelequivalents.com/pt-br/materiais/din-en/c40e.md hi: https://steelequivalents.com/hi/सामग्री/din-en/c40e.md content_hash: sha256:77b21acd60eac2ca3d8da477ff8d4e7bb1ce918c875a35a2d65177cbe53339e9 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/din-en/c40e > Canonical URL: https://steelequivalents.com/materials/din-en/c40e > 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. DIN / EN · Europe · 25 designations # C40E C40E is a material in the category [Quenched and tempered steels](/categories/quenched-and-tempered-steels "Quenched and tempered steels"), held under material number 1.1186. We list 24 designations recorded for this grade, in the standards DIN / EN, UNS, AISI / SAE, BS, AFNOR, UNE, ISO, JIS, GOST, UNI, ČSN, PN, STN, COPANT, MKE, MSZ and AS / NZS. Its recorded composition includes C 0.37–0.44%, Si ≤ 0.4%, Cr ≤ 0.4%, Mn 0.5–0.8% and Ni ≤ 0.4%. Recorded mechanical properties include Rm 530–1000 N/mm², A 6–17% and HB 163–211; these figures vary with the delivery condition and dimension. Its recorded density is 7.85 g/cm³. - [*Material no.* **1.1186**](/materials/material-no/1.1186 "Material no.: 1.1186") - [*Category* **Quenched and tempered steels · 133 grades**](/categories/quenched-and-tempered-steels "Category: Quenched and tempered steels · 133 grades") - *Designations* **25** [Search](/search "Steel grade search")[Inquiry](/inquiry?material=a454c082-ebd3-42ad-8323-386bfc4c0fb6&designation=1b35fa7e-bb67-4b4a-a94e-e2c8287a8485 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/din-en/c40e.pdf "Datasheet as PDF") ## If you came for one of these The most-used names for this grade. - [UNS G10400 This grade’s own name · 5 grades on that route](/materials/uns/g10400 "UNS G10400") - [AISI / SAE 1040 This grade’s own name · 6 grades on that route](/materials/aisi-sae/1040 "AISI / SAE 1040") ## About Quenched and tempered steels Quenched and tempered steels are heat-treated steels designed to combine high strength with useful toughness and ductility. They are used for heavily loaded components such as shafts, gears, fasteners and structural machine parts where resistance to mechanical stress is required. This describes the material class as a whole. Always confirm the individual grade against the standard before ordering. ## Also known as 25 designations · 17 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 - **C40E This grade’s own name** - [Ck 40 This grade’s own name Withdrawn](/materials/din-en/ck40 "DIN / EN Ck 40") UNS United States · 1 - [G10400 This grade’s own name](/materials/uns/g10400 "UNS G10400") AISI / SAE United States · 1 - [1040 This grade’s own name](/materials/aisi-sae/1040 "AISI / SAE 1040") BS United Kingdom · 4 - [060A40 Indicative](/materials/bs/060a40 "BS 060A40") - [080A40 Indicative](/materials/bs/080a40 "BS 080A40") - [080M40 Indicative](/materials/bs/080m40 "BS 080M40") - [CS40 Indicative](/materials/bs/cs40 "BS CS40") AFNOR France · 4 - **C40E Indicative** - [XC 42 Indicative](/materials/afnor/xc42 "AFNOR XC 42") - [XC38H1 Indicative](/materials/afnor/xc38h1 "AFNOR XC38H1") - [XC42H1 Indicative](/materials/afnor/xc42h1 "AFNOR XC42H1") UNE Spain · 1 - [C35k Indicative](/materials/une/c35k "UNE C35k") ISO International · 1 - [C40E4 Indicative](/materials/iso/c40e4 "ISO C40E4") JIS Japan · 1 - [S 40C Indicative](/materials/jis/s40c "JIS S 40C") GOST Russia / CIS · 2 - [40 Indicative](/materials/gb/40 "GOST 40") - [ст.40 Indicative](/materials/gost/st-40 "GOST ст.40") UNI Italy · 1 - [C40 Indicative](/materials/din-en/c40 "UNI C40") ČSN Czechia · 1 - [12041 Indicative](/materials/csn/12041 "ČSN 12041") COPANT Latin America · 1 - [1040 Indicative](/materials/aisi-sae/1040 "COPANT 1040") STN Slovakia · 1 - [12 041 Indicative](/materials/csn/12041 "STN 12 041") PN Poland · 1 - [40 Indicative](/materials/gb/40 "PN 40") MKE Türkiye · 1 - [Ç 1040 Indicative](/materials/mke/c-1040 "MKE Ç 1040") MSZ Hungary · 1 - [C 40 Indicative](/materials/din-en/c40 "MSZ C 40") AS / NZS Australia / New Zealand · 1 - [1040 Indicative](/materials/aisi-sae/1040 "AS / NZS 1040") 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 C Si Iron — the balance, never listed by a standard — 97.6 % Mn — 0.7 % C — 0.4 % Si — 0.4 % Traces & impurities · 1 % Logarithmic scale, 0.01 % to 100 % — every value here compares directly, decade by decade. | Element | % by weight | |---|---| | C | 0.37–0.44 | | Si | ≤ 0.4 | | Mn | 0.5–0.8 | | P | 0.03 | | S | 0.035 | | Cr | ≤ 0.4 | | Mo | ≤ 0.1 | | Ni | ≤ 0.4 | 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 | 0,37-0,44 | 0.370 | 0.440 | Range | | Si | ≤0,40 | — | 0.400 | Max | | P | 0,03 | 0.030 | 0.030 | Exact | | S | 0,035 | 0.035 | 0.035 | Exact | | Cr | ≤0,40 | — | 0.400 | Max | | Mn | 0,50-0,80 | 0.500 | 0.800 | Range | | Ni | ≤0,40 | — | 0.400 | Max | | Mo | ≤0,10 | — | 0.100 | Max | 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 774 °C Predicted Ae1 724 °C Predicted Acm 603 °C Predicted Bs 560 °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. ## Properties by condition 7 conditions · 22 values By thickness**Cold drawn / hard** source `steelnumber` | Thickness mm | Rm N/mm² | A% | |---|---|---| | 5 – 10 | 700 – 1000 | 6 | | 10 – 16 | 650 – 980 | 7 | | 16 – 40 | 620 – 920 | 8 | | 40 – 63 | 590 – 840 | 9 | | 63 – 100 | 550 – 820 | 9 | By thickness**Normalized** source `steelnumber` | Thickness mm | Rm N/mm² | A% | |---|---|---| | ≤ 16 | 580 | 16 | | 16 – 100 | 550 | 17 | | 100 – 250 | 530 | 17 | By thickness**Soft annealed** source `steelnumber` | Thickness mm | Rm N/mm² | A80% | |---|---|---| | 0.3 – 3 | 550 | 18 | By thickness**Cold rolled** source `steelnumber` | Thickness mm | Rm N/mm² | |---|---| | 0.3 – 3 | 970 | By delivery state**As rolled and turned** source `steelnumber` | Delivery state | HB | |---|---| | As rolled and turned | 163 – 211 | By delivery state**Cold rolled** source `steelnumber` | Delivery state | HV | |---|---| | Cold rolled | 280 | By delivery state**Soft annealed** source `steelnumber` | Delivery state | HV | |---|---| | Soft annealed | 170 | 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 1.1, a shared category, and a published range for Mn / Si 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. [C30E 1.1178 Mn 0,50-0,80 · Si ≤0,40 - ΔMn 0.00 - ΔSi 0.00 - 19 designations](/materials/din-en/c30e "C30E")[C30R 1.1179 Mn 0,50-0,80 · Si ≤0,40 - ΔMn 0.00 - ΔSi 0.00 - 11 designations](/materials/din-en/c30r "C30R")[C35 1.1180 Mn 0,50-0,80 · Si ≤0,40 - ΔMn 0.00 - ΔSi 0.00 - 17 designations](/materials/din-en/c35 "C35")[C35E 1.1181 Mn 0,50-0,80 · Si ≤0,40 - ΔMn 0.00 - ΔSi 0.00 - 36 designations](/materials/din-en/c35e "C35E")[C40R 1.1189 Mn 0,50-0,80 · Si ≤0,40 - ΔMn 0.00 - ΔSi 0.00 - 14 designations](/materials/din-en/c40r "C40R")[1.1191 1.1191 Mn 0,50-0,80 · Si ≤0,40 - ΔMn 0.00 - ΔSi 0.00 - 39 designations](/materials/material-no/1.1191 "1.1191") ## 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=a454c082-ebd3-42ad-8323-386bfc4c0fb6&designation=1b35fa7e-bb67-4b4a-a94e-e2c8287a8485 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/din-en/c40e.pdf "Datasheet as PDF")