--- title: "S31783 — X2CrNiMo18-16-5, 3 equivalent designations" description: "S31783 in UNS: material number 1.4440, also listed as X2CrNiMo18-16-5. It is a material in the category Others. 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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 · 3 designations # S31783 S31783 is a designation in UNS for the material held under material number 1.4440, also listed as X2CrNiMo18-16-5. It is a material in the category Others. We list 3 designations recorded for this grade, in the standards DIN / EN and UNS. - [*Material no.* **1.4440**](/materials/material-no/1.4440 "Material no.: 1.4440") - [*Category* **Others · 1754 grades**](/categories/others "Category: Others · 1754 grades") - *Designations* **3** [Search](/search "Steel grade search")[Inquiry](/inquiry?material=ceda43cb-c665-470f-bb22-5a7ab44e0e34&designation=7d74e1d7-7d64-4ab1-8695-e575517cbea3 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/uns/s31783.pdf "Datasheet as PDF") ## If you came for one of these The most-used names for this grade. - [DIN / EN X2CrNiMo18-16-5 This grade’s own name](/materials/din-en/x2crnimo18-16-5 "DIN / EN X2CrNiMo18-16-5") - [UNS S31780 This grade’s own name](/materials/uns/s31780 "UNS S31780") ## About Others These are miscellaneous metallic alloys that do not fit a more specific material family and may be based on iron, nickel, cobalt, copper or other alloy systems. They are selected for applications requiring particular combinations of strength, hardness, toughness, wear resistance or resistance to demanding service conditions. This describes the material class as a whole. Always confirm the individual grade against the standard before ordering. ## Also known as 3 designations · 2 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 Withdrawn designation no longer current — a separate column from the two above, so a name can be same grade and withdrawn at once.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 - [X2CrNiMo18-16-5 This grade’s own name](/materials/din-en/x2crnimo18-16-5 "DIN / EN X2CrNiMo18-16-5") UNS United States · 2 - [S31780 This grade’s own name](/materials/uns/s31780 "UNS S31780") - **S31783 This grade’s own name** 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 Cr Ni Mo Iron — the balance, never listed by a standard — 55.9 % Cr — 18.5 % Ni — 17.5 % Mo — 4.5 % Traces & impurities · 3.6 % Logarithmic scale, 0.01 % to 100 % — every value here compares directly, decade by decade. | Element | % by weight | |---|---| | C | ≤ 0.03 | | Si | ≤ 1 | | Mn | 2–3 — Unusual | | P | 0.025 | | S | 0.025 | | Cr | 17–20 | | Mo | 4–5 | | Ni | 16–19 | 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 | ≤0,030 | — | 0.030 | Max | | Si | ≤1,00 | — | 1.000 | Max | | P | 0,025 | 0.025 | 0.025 | Exact | | S | 0,025 | 0.025 | 0.025 | Exact | | Cr | 17,0-20,0 | 17.000 | 20.000 | Range | | Mn | 2,00-3,00 | 2.000 | 3.000 | Range | | Ni | 16,0-19,0 | 16.000 | 19.000 | Range | | Mo | 4,00-5,00 | 4.000 | 5.000 | 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 This grade's composition falls outside the published model's validated range (a low-alloy composition window), so no transformation temperature is predicted here. ## 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 1.4, a shared category, and a published range for Cr / 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. [X3CrNiMnMoN19-16 1.4453 Cr 16,0-20,0 · Ni 15,0-17,5 - ΔCr 0.50 - ΔNi 1.25 - 1 designations](/materials/din-en/x3crnimnmon19-16 "X3CrNiMnMoN19-16")[X2CrNiMoN18-15-5 1.4483 Cr 17,0-20,0 · Ni 13,5-17,5 - ΔCr 0.00 - ΔNi 2.00 - 3 designations](/materials/din-en/x2crnimon18-15-5 "X2CrNiMoN18-15-5")[X3CrNiMo18-16-5 1.4476 Cr 16,0-19,0 · Ni 15,0-17,0 - ΔCr 1.00 - ΔNi 1.50 - 1 designations](/materials/din-en/x3crnimo18-16-5 "X3CrNiMo18-16-5")[GX2CrNiMoCuN20-18-6 1.4557 Cr 19,5-20,5 · Ni 17,5-19,5 - ΔCr 1.50 - ΔNi 1.00 - 9 designations](/materials/din-en/gx2crnimocun20-18-6 "GX2CrNiMoCuN20-18-6")[X3NiCr18-16 1.4389 Cr 15,0-17,0 · Ni 17,0-19,0 - ΔCr 2.50 - ΔNi 0.50 - 12 designations](/materials/din-en/x3nicr18-16 "X3NiCr18-16")[X2CrNiMnMoN20-16 1.4455 Cr 18,2-21,3 · Ni 14,2-16,3 - ΔCr 1.25 - ΔNi 2.25 - 2 designations](/materials/din-en/x2crnimnmon20-16 "X2CrNiMnMoN20-16") ## 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=ceda43cb-c665-470f-bb22-5a7ab44e0e34&designation=7d74e1d7-7d64-4ab1-8695-e575517cbea3 "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/uns/s31783.pdf "Datasheet as PDF")