--- title: "CFS5 — Unalloyed structural steels" description: "CFS5 in BS: material number 1.0580, also listed as St 52-3. Category: Unalloyed structural steels. 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Compare it to detect a real > content change; `generated` moves on every render and is not a change signal. BS · United Kingdom · 26 designations # CFS5 CFS5 is a designation in BS for the material held under material number 1.0580, also listed as St 52-3. It is a material in the category Unalloyed structural steels. We list 26 designations recorded for this grade, in the standards DIN / EN, AISI / SAE, BS, AFNOR, ISO, GOST, UNI, SS, ČSN, PN and ÖNORM. - [*Material no.* **1.0580**](/materials/material-no/1.0580 "Material no.: 1.0580") - [*Category* **Unalloyed structural steels · 452 grades**](/categories/unalloyed-structural-steels "Category: Unalloyed structural steels · 452 grades") - *Designations* **26** [Search](/search "Steel grade search")[Inquiry](/inquiry?material=ab035a27-b7ea-4c83-b1fb-7685dbc98258&designation=e01b3468-9af5-4f4d-aa42-97c821bab1b9 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/bs/cfs5.pdf "Datasheet as PDF") ## If you came for one of these The most-used names for this grade. - [DIN / EN E355 This grade’s own name](/materials/din-en/e355 "DIN / EN E355") - [AISI / SAE 1024 This grade’s own name · 5 grades on that route](/materials/aisi-sae/1024 "AISI / SAE 1024") ## About Unalloyed structural steels Unalloyed structural steels include all low-carbon steels in which the iron companions do not exceed specified minimum values. The yield strength, formability and weldability are the decisive factors for their use. They are soft, pliable, tough and stretchy, but cannot be hardened by heat treatment. This describes the material class as a whole. Always confirm the individual grade against the standard before ordering. ## Also known as 26 designations · 11 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 Withdrawn designation no longer current — a separate column from the two above, so a name can be same grade and withdrawn at once. Superseded by the current name this withdrawn designation was replaced by — the same grade under its present designation, the one to order by today. DIN / EN Europe · 5 - [1.0060 Indicative](/materials/material-no/1.0060 "DIN / EN 1.0060") - [E355 This grade’s own name](/materials/din-en/e355 "DIN / EN E355") - [S355GT This grade’s own name](/materials/din-en/s355gt "DIN / EN S355GT")Formerly St 52 - [St 52 This grade’s own name Withdrawn](/materials/din-en/st-52 "DIN / EN St 52")Superseded by[S355GT](/materials/din-en/s355gt "S355GT") - [St 52-3 This grade’s own name](/materials/din-en/st52-3 "DIN / EN St 52-3") AISI / SAE United States · 2 - [1024 This grade’s own name](/materials/aisi-sae/1024 "AISI / SAE 1024") - [Gr.65 Indicative](/materials/aisi-sae/gr-65 "AISI / SAE Gr.65") BS United Kingdom · 5 - [CEW5 Indicative](/materials/bs/cew5 "BS CEW5") - **CFS5 Indicative** - [E335 Indicative](/materials/din-en/e335 "BS E335") - [ERW5NKM Indicative](/materials/bs/erw5nkm "BS ERW5NKM") - [ERW5NZF Indicative](/materials/bs/erw5nzf "BS ERW5NZF") AFNOR France · 4 - [E335 Indicative](/materials/din-en/e335 "AFNOR E335") - [ES355 Indicative](/materials/afnor/es355 "AFNOR ES355") - [TS-47a Indicative](/materials/afnor/ts-47a "AFNOR TS-47a") - [TU526 Indicative](/materials/afnor/tu526 "AFNOR TU526") ISO International · 1 - [Fe590 Indicative](/materials/uni/fe590 "ISO Fe590") GOST Russia / CIS · 1 - [St6sp Indicative](/materials/gost/st6sp "GOST St6sp") UNI Italy · 2 - [E335 Indicative](/materials/din-en/e335 "UNI E335") - [Fe510 Indicative](/materials/bs/fe510 "UNI Fe510") SS Sweden · 1 - [1650 Indicative](/materials/ss/1650 "SS 1650") ČSN Czechia · 3 - [11 523 Indicative](/materials/csn/11523 "ČSN 11 523") - [11483 Indicative](/materials/csn/11483 "ČSN 11483") - [11600 Indicative](/materials/csn/11600 "ČSN 11600") PN Poland · 1 - [MSt6 Indicative](/materials/pn/mst6 "PN MSt6") ÖNORM Austria · 1 - [St60F Indicative](/materials/onorm/st60f "ÖNORM St60F") Every designation on file is listed — no truncation, no “+ n more”. Each one is itself a route that leads back here. ## Chemical composition 5 elements on file · weight % What this alloy is Fe Mn Si C Iron — the balance, never listed by a standard — 97.6 % Mn — 1.6 % Si — 0.6 % C — 0.2 % Traces & impurities · 0 % Logarithmic scale, 0.01 % to 100 % — every value here compares directly, decade by decade. | Element | % by weight | |---|---| | C | ≤ 0.22 | | Si | ≤ 0.55 | | Mn | ≤ 1.6 | | P | 0.025 | | S | 0.025 | Carbon Silicon Manganese Phosphorus Sulfur 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 | ≤0,22 | — | 0.220 | Max | | Si | ≤0,55 | — | 0.550 | Max | | P | 0,025 | 0.025 | 0.025 | Exact | | S | 0,025 | 0.025 | 0.025 | Exact | | Mn | ≤1,60 | — | 1.600 | Max | - Al, Nb, Ti oder V - Al, Nb, Ti oder V - Al, Nb, Ti oder V 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, Mo. ## Physical & mechanical properties Density 7,85 g/cm³ Exact Weldability weldable with restrictions As published: limited weldability. Flake sensitivity not susceptible As published: not predisposed Temper brittleness not susceptible As published: not predisposed 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 3 conditions · 16 values By thickness**As rolled** source `steelnumber` | Thickness mm | ReH N/mm² | Rm N/mm² | |---|---|---| | ≤ 16 | 355 | 490 | | 16 – 40 | 345 | 490 | | 40 – 65 | 335 | 490 | | 65 – 100 | — | 470 | | 65 – 80 | 315 | — | | 80 – 100 | 295 | — | By delivery state**no delivery state stated** source `splav` | Delivery state | Rm N/mm² | Re N/mm² | A5% | |---|---|---|---| | Pipe, GOST 8731-87 | 588 | 304 | 14 | | Rolled stock, GOST 535-2005 | 590 | 295 – 315 | 12 – 15 | At temperature**no delivery state stated** source `splav` | Temperature °C | Density g/cm³ | |---|---| | 20 | 7.85 | 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 1.0, 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. [S355JR 1.0045 Mn ≤1,60 · Si ≤0,55 - ΔMn 0.00 - ΔSi 0.00 - 32 designations](/materials/din-en/s355jr "S355JR")[S320GP 1.0046 Mn ≤1,60 · Si ≤0,55 - ΔMn 0.00 - ΔSi 0.00 - 3 designations](/materials/din-en/s320gp "S320GP")[S355GP 1.0083 Mn ≤1,60 · Si ≤0,55 - ΔMn 0.00 - ΔSi 0.00 - 5 designations](/materials/din-en/s355gp "S355GP")[P235G1T1 1.0253 Mn ≤1,60 · Si ≤0,55 - ΔMn 0.00 - ΔSi 0.00 - 3 designations](/materials/din-en/p235g1t1 "P235G1T1")[P275T1 1.0256 Mn ≤1,60 · Si ≤0,55 - ΔMn 0.00 - ΔSi 0.00 - 7 designations](/materials/din-en/p275t1 "P275T1")[E370 1.0261 Mn ≤1,60 · Si ≤0,55 - ΔMn 0.00 - ΔSi 0.00 - 2 designations](/materials/din-en/e370 "E370") ## 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=ab035a27-b7ea-4c83-b1fb-7685dbc98258&designation=e01b3468-9af5-4f4d-aa42-97c821bab1b9 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/bs/cfs5.pdf "Datasheet as PDF")