--- title: "K03103 — Heat-resistant structural steels" description: "K03103 in UNS: material number 1.0473, also listed as 19Mn6. Category: Heat-resistant 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. UNS · United States · 26 designations # K03103 K03103 is a designation in UNS for the material held under material number 1.0473, also listed as 19Mn6. It is a material in the category Heat-resistant structural steels. We list 26 designations recorded for this grade, in the standards DIN / EN, UNS, AISI / SAE, ASTM, BS, AFNOR, UNE, JIS, UNI, SS and SFS. - [*Material no.* **1.0473**](/materials/material-no/1.0473 "Material no.: 1.0473") - [*Category* **Heat-resistant structural steels · 62 grades**](/categories/heat-resistant-structural-steels "Category: Heat-resistant structural steels · 62 grades") - *Designations* **26** [Search](/search "Steel grade search")[Inquiry](/inquiry?material=f99767d6-fd59-4b40-b550-4c242f055075&designation=a1d76eaa-7644-4e51-ad90-2ed621265872 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/uns/k03103.pdf "Datasheet as PDF") ## If you came for one of these The most-used names for this grade. - [DIN / EN 19Mn6 This grade’s own name · 2 grades on that route](/materials/din-en/19mn6 "DIN / EN 19Mn6") - [UNS K02700 This grade’s own name · 9 grades on that route](/materials/uns/k02700 "UNS K02700") ## About Heat-resistant structural steels Heat-resistant structural steels are structural steels designed to retain useful strength and dimensional stability at elevated temperatures. They are used for load-bearing components in hot-service equipment where mechanical performance must be maintained during heating. 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 Withdrawn designation no longer current — a separate column from the two above, so a name can be same grade and withdrawn at once. DIN / EN Europe · 3 - [19Mn6 This grade’s own name](/materials/din-en/19mn6 "DIN / EN 19Mn6") - [A537CL1 Indicative](/materials/din-en/a537cl1 "DIN / EN A537CL1") - [P355GH This grade’s own name](/materials/din-en/p355gh "DIN / EN P355GH") UNS United States · 5 - [K02700 This grade’s own name](/materials/uns/k02700 "UNS K02700") - [K02803 This grade’s own name](/materials/uns/k02803 "UNS K02803") - **K03103 This grade’s own name** - [K03300 This grade’s own name](/materials/uns/k03300 "UNS K03300") - [K12437 Indicative](/materials/uns/k12437 "UNS K12437") AISI / SAE United States · 4 - [A414Gr.G Indicative](/materials/aisi-sae/a414gr-g "AISI / SAE A414Gr.G") - [A516Gr.70 Indicative](/materials/aisi-sae/a516gr-70 "AISI / SAE A516Gr.70") - [A537 Indicative](/materials/aisi-sae/a537 "AISI / SAE A537") - [A537CL1 Indicative](/materials/din-en/a537cl1 "AISI / SAE A537CL1") ASTM United States · 1 - [A537 Indicative](/materials/aisi-sae/a537 "ASTM A537") BS United Kingdom · 1 - [224Gr.490 Indicative](/materials/bs/224gr-490 "BS 224Gr.490") AFNOR France · 3 - [A52CP Indicative](/materials/afnor/a52cp "AFNOR A52CP") - [AP Indicative](/materials/afnor/ap "AFNOR AP") - [P335GH Indicative](/materials/afnor/p335gh "AFNOR P335GH") UNE Spain · 2 - [A 47 RB II Indicative](/materials/une/a-47-rb-ii "UNE A 47 RB II") - [A52RCI Indicative](/materials/une/a52rci "UNE A52RCI") JIS Japan · 1 - [SPV36 Indicative](/materials/jis/spv36 "JIS SPV36") UNI Italy · 1 - [Fe510-1KW Indicative](/materials/uni/fe510-1kw "UNI Fe510-1KW") SS Sweden · 3 - [2101 Indicative](/materials/ss/2101 "SS 2101") - [2102 Indicative](/materials/ss/2102 "SS 2102") - [2103 Indicative](/materials/ss/2103 "SS 2103") SFS Finland · 2 - [Fe52BP Indicative](/materials/sfs/fe52bp "SFS Fe52BP") - [Fe52DP Indicative](/materials/sfs/fe52dp "SFS Fe52DP") Every designation on file is listed — no truncation, no “+ n more”. Each one is itself a route that leads back here. ## Chemical composition 14 elements on file · weight % What this alloy is Fe Mn Si Cr Iron — the balance, never listed by a standard — 96.8 % Mn — 1.4 % Si — 0.6 % Cr — 0.3 % Traces & impurities · 1 % Logarithmic scale, 0.01 % to 100 % — every value here compares directly, decade by decade. | Element | % by weight | |---|---| | C | 0.1–0.22 | | Si | ≤ 0.6 | | Mn | 1–1.7 | | P | 0.025 | | S | 0.01 | | Cr | ≤ 0.3 | | Mo | ≤ 0.08 | | Ni | ≤ 0.3 | | V | ≤ 0.02 | | Cu | ≤ 0.3 | | Al | ≥ 0.02 | | Ti | ≤ 0.03 | | Nb | ≤ 0.02 | | N | 0.012 | Carbon Silicon Manganese Phosphorus Sulfur Chromium Molybdenum Nickel Vanadium Copper Aluminium Titanium Niobium Nitrogen 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 | 0,10-0,22 | 0.100 | 0.220 | Range | | N | 0,012 | 0.012 | 0.012 | Exact | | Al | ≥0,020 | 0.020 | — | Min | | Si | ≤0,60 | — | 0.600 | Max | | P | 0,025 | 0.025 | 0.025 | Exact | | S | 0,01 | 0.010 | 0.010 | Exact | | Ti | ≤0,03 | — | 0.030 | Max | | V | ≤0,02 | — | 0.020 | Max | | Cr | ≤0,30 | — | 0.300 | Max | | Mn | 1,00-1,70 | 1.000 | 1.700 | Range | | Ni | ≤0,30 | — | 0.300 | Max | | Cu | ≤0,30 | — | 0.300 | Max | | Nb | ≤0,02 | — | 0.020 | Max | | Mo | ≤0,08 | — | 0.080 | 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 812 °C Predicted Ae1 715 °C Predicted Acm 457 °C Predicted Bs 547 °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 1 conditions · 10 values By thickness**Normalized** source `steelnumber` | Thickness mm | ReH N/mm² | Rm N/mm² | |---|---|---| | ≤ 16 | 355 | — | | 16 – 40 | 345 | — | | 40 – 60 | 335 | — | | ≤ 60 | — | 510 – 650 | | 60 – 100 | 315 | 490 – 630 | | 100 – 150 | 295 | 480 – 630 | | 150 – 250 | 280 | 470 – 630 | 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. [21Mn6 1.0485 Mn 1,15-1,60 · Si ≤0,60 - ΔMn 0.02 - ΔSi 0.00 - 4 designations](/materials/din-en/21mn6 "21Mn6")[1.0436 1.0481 Mn 0,90-1,50 · Si ≤0,40 - ΔMn 0.15 - ΔSi 0.10 - 83 designations](/materials/material-no/1.0436 "1.0436")[1.0425 1.0425 Mn 0,80-1,40 · Si ≤0,40 - ΔMn 0.25 - ΔSi 0.10 - 79 designations](/materials/material-no/1.0425 "1.0425")[19Mn5 1.0482 Mn 1,00-1,30 · Si 0,30-0,60 - ΔMn 0.20 - ΔSi 0.15 - 9 designations](/materials/din-en/19mn5 "19Mn5")[P285NH 1.0477 Mn 0,60-1,40 · Si ≤0,40 - ΔMn 0.35 - ΔSi 0.10 - 3 designations](/materials/din-en/p285nh "P285NH")[1.0345 1.0345 Mn 0,60-1,20 · Si ≤0,35 - ΔMn 0.45 - ΔSi 0.13 - 62 designations](/materials/material-no/1.0345 "1.0345") ## 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=f99767d6-fd59-4b40-b550-4c242f055075&designation=a1d76eaa-7644-4e51-ad90-2ed621265872 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/uns/k03103.pdf "Datasheet as PDF")