--- title: "SUS303 — Stainless steels" description: "SUS303 in JIS: material number 1.4305, also listed as X8CrNiS18-9. Category: Stainless steels. 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Compare it to detect a real > content change; `generated` moves on every render and is not a change signal. JIS · Japan · 77 designations # SUS303 SUS303 is a designation in JIS for the material held under material number 1.4305, also listed as X8CrNiS18-9. It is a material in the category Stainless steels. We list 77 designations recorded for this grade, in the standards DIN / EN, UNS, AISI / SAE, ASTM, BS, AFNOR, UNE, SAE AMS, JIS, GB, GOST, UNI, SS, ČSN, PN, STN, SRPS and JUS. - [*Material no.* **1.4305**](/materials/material-no/1.4305 "Material no.: 1.4305") - [*Category* **Stainless steels · 468 grades**](/categories/stainless-steels "Category: Stainless steels · 468 grades") - *Designations* **77** [Search](/search "Steel grade search")[Inquiry](/inquiry?material=c6fc1652-e60a-4633-aefa-d24e70c6d7cf&designation=b50b971b-86fe-4515-806f-48cade679d6f "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/jis/sus303.pdf "Datasheet as PDF") ## If you came for one of these The most-used names for this grade. - [DIN / EN X10CrNiS189 This grade’s own name](/materials/din-en/x10crnis189 "DIN / EN X10CrNiS189") - [UNS S30300 This grade’s own name · 6 grades on that route](/materials/uns/s30300 "UNS S30300") - [AISI / SAE 303 This grade’s own name · 7 grades on that route](/materials/aisi-sae/303 "AISI / SAE 303") - [BS 303S22 This grade’s own name](/materials/bs/303s22 "BS 303S22") - [SS SIS 2346 This grade’s own name](/materials/ss/sis-2346 "SS SIS 2346") ## About Stainless steels Stainless steels are corrosion-resistant alloy steels whose chromium content promotes a protective passive surface film. They are used for equipment, structures and components exposed to moisture, chemicals or hygienic service, with different alloy compositions selected for corrosion resistance, strength, formability or weldability. This describes the material class as a whole. Always confirm the individual grade against the standard before ordering. ## Also known as 77 designations · 18 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 · 5 - [1.4305 Indicative](/materials/material-no/1.4305 "DIN / EN 1.4305") - [X 10 CrNiS 18 9 This grade’s own name Withdrawn](/materials/din-en/x10crnis189 "DIN / EN X 10 CrNiS 18 9") - [X10CrNiS189 This grade’s own name](/materials/din-en/x10crnis189 "DIN / EN X10CrNiS189") - [X12CrNiS188 Indicative](/materials/din-en/x12crnis188 "DIN / EN X12CrNiS188") - [X8CrNiS18-9 This grade’s own name](/materials/din-en/x8crnis18-9 "DIN / EN X8CrNiS18-9") UNS United States · 6 - [S30300 This grade’s own name](/materials/uns/s30300 "UNS S30300") - [S30400 Indicative](/materials/uns/s30400 "UNS S30400") - [S30403 Indicative](/materials/uns/s30403 "UNS S30403") - [S30453 Indicative](/materials/uns/s30453 "UNS S30453") - [S30500 Indicative](/materials/uns/s30500 "UNS S30500") - [S41603 Indicative](/materials/uns/s41603 "UNS S41603") AISI / SAE United States · 8 - [303 This grade’s own name](/materials/aisi-sae/303 "AISI / SAE 303") - [30303 Indicative](/materials/aisi-sae/30303 "AISI / SAE 30303") - [304 Indicative](/materials/aisi-sae/304 "AISI / SAE 304") - [304L Indicative](/materials/aisi-sae/304l "AISI / SAE 304L") - [304LN Indicative](/materials/aisi-sae/304ln "AISI / SAE 304LN") - [305 Indicative](/materials/aisi-sae/305 "AISI / SAE 305") - [416L Indicative](/materials/aisi-sae/416l "AISI / SAE 416L") - [S30300 Indicative](/materials/uns/s30300 "AISI / SAE S30300") ASTM United States · 18 - [A194 Indicative](/materials/astm/a194 "ASTM A194") - [A314 Indicative](/materials/astm/a314 "ASTM A314") - [A320 Indicative](/materials/nbn/a320 "ASTM A320") - [A320 Grade B8F Indicative](/materials/astm/a320-grade-b8f "ASTM A320 Grade B8F") - [A473 Indicative](/materials/astm/a473 "ASTM A473") - [A484 Indicative](/materials/astm/a484 "ASTM A484") - [A581 Indicative](/materials/astm/a581 "ASTM A581") - [A582 Indicative](/materials/astm/a582 "ASTM A582") - [A895 Indicative](/materials/astm/a895 "ASTM A895") - [F593 Indicative](/materials/astm/f593 "ASTM F593") - [F594 Indicative](/materials/astm/f594 "ASTM F594") - [F738 Indicative](/materials/astm/f738 "ASTM F738") - [F836 Indicative](/materials/astm/f836 "ASTM F836") - [F837 Indicative](/materials/astm/f837 "ASTM F837") - [F880 Indicative](/materials/astm/f880 "ASTM F880") - [F899 Indicative](/materials/astm/f899 "ASTM F899") - [TP304 Indicative](/materials/astm/tp304 "ASTM TP304") - [TP304L Indicative](/materials/astm/tp304l "ASTM TP304L") BS United Kingdom · 7 - [301 S 21 Indicative](/materials/bs/301s21 "BS 301 S 21") - [303S21 Indicative](/materials/bs/303s21 "BS 303S21") - [303S21 EN 58M Indicative](/materials/bs/303s21-en-58m "BS 303S21 EN 58M") - [303S22 This grade’s own name](/materials/bs/303s22 "BS 303S22") - [303S31 Indicative](/materials/bs/303s31 "BS 303S31") - [58M Indicative](/materials/bs/58m "BS 58M") - [EN58M Indicative](/materials/bs/en58m "BS EN58M") AFNOR France · 2 - [Z10CNF18.09 Indicative](/materials/afnor/z10cnf18-09 "AFNOR Z10CNF18.09") - [Z8CNF18-09 Indicative](/materials/afnor/z8cnf18-09 "AFNOR Z8CNF18-09") UNE Spain · 7 - [18-09 Indicative](/materials/une/18-09 "UNE 18-09") - [F-3507 Indicative](/materials/une/f-3507 "UNE F-3507") - [F.310.C Indicative](/materials/une/f-310-c "UNE F.310.C") - [F.3504 Indicative](/materials/une/f-3504 "UNE F.3504") - [F.3508 Indicative](/materials/une/f-3508 "UNE F.3508") - [F.3508-X10CrNiS Indicative](/materials/une/f-3508-x10crnis "UNE F.3508-X10CrNiS") - [X10CrNi18-9 Indicative](/materials/une/x10crni18-9 "UNE X10CrNi18-9") SAE AMS United States / Aerospace · 4 - [5635 Indicative bar forging](/materials/ams/5635 "SAE AMS 5635") - [5638 Indicative bar forging wire](/materials/ams/5638 "SAE AMS 5638") - [5640 Indicative bar](/materials/ams/5640 "SAE AMS 5640") - [5641 Indicative bar](/materials/ams/5641 "SAE AMS 5641") JIS Japan · 3 - [SUS 301 Indicative](/materials/jis/sus301 "JIS SUS 301") - [SUS 302 Indicative](/materials/jis/sus302 "JIS SUS 302") - **SUS303 Indicative** GB China · 2 - [1Cr18Ni9MoZr Indicative](/materials/gb/1cr18ni9mozr "GB 1Cr18Ni9MoZr") - [Y1Cr18Ni9 Indicative](/materials/gb/y1cr18ni9 "GB Y1Cr18Ni9") GOST Russia / CIS · 4 - [12Ch18N10E Indicative](/materials/gost/12ch18n10e "GOST 12Ch18N10E") - [12Ch18N9 Indicative](/materials/gost/12ch18n9 "GOST 12Ch18N9") - [12Kh18N9 Indicative](/materials/gost/12kh18n9 "GOST 12Kh18N9") - [2Ch18N10E Indicative](/materials/gost/2ch18n10e "GOST 2Ch18N10E") UNI Italy · 1 - [X10CrNiS18-09 Indicative](/materials/uni/x10crnis18-09 "UNI X10CrNiS18-09") SS Sweden · 2 - [2346 Indicative](/materials/ss/2346 "SS 2346") - [SIS 2346 This grade’s own name](/materials/ss/sis-2346 "SS SIS 2346") ČSN Czechia · 2 - [17 243 PH Indicative](/materials/csn/17-243-ph "ČSN 17 243 PH") - [17243 Indicative](/materials/csn/17243 "ČSN 17243") PN Poland · 3 - [00H18N10 Indicative](/materials/pn/00h18n10 "PN 00H18N10") - [0H18N9 Indicative](/materials/pn/0h18n9 "PN 0H18N9") - [1H18N9 Indicative](/materials/pn/1h18n9 "PN 1H18N9") STN Slovakia · 1 - [17 243 Indicative](/materials/csn/17243 "STN 17 243") SRPS Serbia · 1 - [Č.4590 Indicative](/materials/srps/c-4590 "SRPS Č.4590") JUS former Yugoslavia · 1 - [Č.4590 Indicative](/materials/srps/c-4590 "JUS Č.4590") Every designation on file is listed — no truncation, no “+ n more”. Each one is itself a route that leads back here. ## Chemical composition 9 elements on file · weight % What this alloy is Fe Cr Ni Mn Iron — the balance, never listed by a standard — 68.5 % Cr — 18 % Ni — 9 % Mn — 2 % Traces & impurities · 2.5 % Logarithmic scale, 0.01 % to 100 % — every value here compares directly, decade by decade. | Element | % by weight | |---|---| | C | ≤ 0.1 | | Si | ≤ 1 | | Mn | ≤ 2 | | P | 0.045 | | S | 0.15–0.35 — Unusual | | Cr | 17–19 | | Ni | 8–10 | | Cu | ≤ 1 | | N | 0.11 | Carbon Silicon Manganese Phosphorus Sulfur Chromium Nickel Copper 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 | — | 0.100 | Max | | N | 0,11 | 0.110 | 0.110 | Exact | | Si | ≤1,00 | — | 1.000 | Max | | P | 0,045 | 0.045 | 0.045 | Exact | | S | 0,15-0,35 | 0.150 | 0.350 | Range | | Cr | 17,0-19,0 | 17.000 | 19.000 | Range | | Mn | ≤2,00 | — | 2.000 | Max | | Ni | 8,00-10,0 | 8.000 | 10.000 | Range | | Cu | ≤1,00 | — | 1.000 | 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 Not enough recorded composition to predict a transformation temperature for this grade — missing: Mo. ## Physical & mechanical properties Density 7,9 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 2 conditions · 11 values By delivery state**no delivery state stated** source `steeljis` | Delivery state | Rm N/mm² | Re N/mm² | A% | Z% | HB | HRB | HV | |---|---|---|---|---|---|---|---| | Plate/Sheet Hot-rolled | 520 | 205 | 35 | — | — | — | — | | Bars/Rods | 520 | 205 | 40 | 50 | — | — | — | | Hot-rolled | — | — | — | — | 187 | 90 | 200 | By delivery state**Soft annealed** source `steelnumber` | Delivery state | HB | |---|---| | Soft annealed | 230 | 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 1.4, 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. [X 12 CrNi 18 8 1.4300 Cr 17,0-19,0 · Ni 8,00-10,0 - ΔCr 0.00 - ΔNi 0.00 - 76 designations](/materials/din-en/x-12-crni-18-8 "X 12 CrNi 18 8")[X9CrNi18-9 1.4325 Cr 17,0-19,0 · Ni 8,00-10,0 - ΔCr 0.00 - ΔNi 0.00 - 51 designations](/materials/din-en/x9crni18-9 "X9CrNi18-9")[X3CrNiCu18-9-4 1.4567 Cr 17,0-19,0 · Ni 8,50-10,5 - ΔCr 0.00 - ΔNi 0.50 - 16 designations](/materials/din-en/x3crnicu18-9-4 "X3CrNiCu18-9-4")[1.4301 1.4301 Cr 17,5-19,5 · Ni 8,00-10,5 - ΔCr 0.50 - ΔNi 0.25 - 170 designations](/materials/material-no/1.4301 "1.4301")[1.4307 1.4307 Cr 17,5-19,5 · Ni 8,00-10,5 - ΔCr 0.50 - ΔNi 0.25 - 88 designations](/materials/material-no/1.4307 "1.4307")[X15CrNiMn18-8 1.4370 Cr 17,2-19,8 · Ni 7,60-9,40 - ΔCr 0.50 - ΔNi 0.50 - 1 designations](/materials/din-en/x15crnimn18-8 "X15CrNiMn18-8") ## 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=c6fc1652-e60a-4633-aefa-d24e70c6d7cf&designation=b50b971b-86fe-4515-806f-48cade679d6f "Inquiry")[**Datasheet as PDF** Print-ready A4 document **Generating …** **Download started** **Try again**](/materials/jis/sus303.pdf "Datasheet as PDF")