Stainless Steel 1.4424
EN 1.4424 · UNS S31500 · also 3RE60
EN 1.4424 (UNS S31500, 3RE60, X2CrNiMoSi18-5-3) is an early silicon-alloyed duplex stainless of 18Cr-5Ni-3Mo-Si developed for resistance to stress corrosion cracking in sulfuric and sulfite environments.
Reference datasheet — 1.4424 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the SA-CR condition
1.4424 tempers and conditions
1.4424 is supplied in 4 conditions, soft to hard. SA-CR is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed, hot rolled | Choose for plate ≥6 mm, vessel shells and hot-finished bar; slightly lower strength and rougher pickled surface than cold-rolled product. | 465 | 690 | 32 | 19 HRC | — |
As-welded deposit | Property set for weldments left as-welded; use overalloyed 2209-type filler and controlled heat input to restore austenite balance, otherwise toughness and pitting resistance fall. | 470 | 690 | 25 | 22 HRC | 2.2 % IACS |
SA-CRDefault Solution annealed, cold rolled | Default stocked condition for sheet and strip: solution annealed ~1020–1100 °C, water quenched, cold-rolled 2B finish for vessels and heat-exchanger fabrication. | 490 | 700 | 35 | 21 HRC | — |
Cold drawn | Pick when higher yield strength and tighter dimensional tolerance are needed on bar or small-bore tube; ductility and impact energy drop. | 650 | 820 | 20 | 28 HRC | — |
Supply forms, finishes and certifications
Ways 1.4424 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
SA-TUBE | Solution annealed seamless tube/pipe | Supply form |
What is 1.4424?
EN 1.4424 (UNS S31500, 3RE60, X2CrNiMoSi18-5-3) is an early silicon-alloyed duplex stainless of 18Cr-5Ni-3Mo-Si developed for resistance to stress corrosion cracking in sulfuric and sulfite environments. Solution-annealed cold- and hot-rolled sheet, tube, cold-drawn bar and as-welded tube provide 490 MPa yield, 700 MPa tensile and 35 % elongation at 230 HB, with a corrosion score of 68 and weldability rated 70. Machinability is low (score 30), service tops out near 280 °C and stock availability is limited; 1.4462 (2205) is the current equivalent for most new work. 1.4424 has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,400°C (2,552 °F). 1.4424 has a yield strength of 490 MPa (71.1 ksi) and a tensile strength of 700 MPa (102 ksi) — stronger than 76% of stainless steel grades. Elongation at break is 35% and the elastic modulus is 200 GPa (29 Msi).
What is 1.4424 used for?
- pulp and paper digesters
- heat exchangers
- sulfite liquor equipment
Advantages
- High strength — 490 MPa (71.1 ksi), better than 76% of stainless steel grades
Limitations
- Limited service temperature — 280°C (536 °F), worse than 96% of stainless steel grades
1.4424 properties
Typical room-temperature values for 1.4424-SA-CR; bars are the position among stainless steel grades.
Physical3
1.4424 has a density of 7.75 g/cm³ (0.28 lb/in³), lighter than 65% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical17
1.4424 has a yield strength of 490 MPa (71.1 ksi) and a tensile strength of 700 MPa (102 ksi) — stronger than 76% of stainless steel grades. Elongation at break is 35% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
1.4424 is rated for continuous service to 280°C (536 °F). It conducts heat at 16 W/m·K (9.24 BTU/hr·ft·°F), better than 58% of stainless steel grades. Thermal expansion is 13 µm/m·K (7.22 µin/in·°F).
Electrical3
1.4424 conducts electricity at 2.2 % IACS, worse than 61% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (68/100), better than 63% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4424 takes about 52 MJ of energy and emits 4.2 kg of CO₂ — less than 76% of stainless steel grades. Typical recycled content is 65%.
Manufacturability8
1.4424's machinability is poor (30/100, worse than 70% of stainless steel grades); weldability very good (70/100); formability good (55/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the stainless steel family
Yield strength against density for every stainless steel grade FabDigit runs. 1.4424 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 1.4424
Is 1.4424 easy to machine?
Machines like a work-hardening duplex: ~25 % of 1212, use rigid setups, positive-rake coated carbide, heavy positive feeds and generous coolant to stay under the hardened layer.
Can 1.4424 be welded?
Weldable by GTAW/GMAW/SAW with overalloyed 22 %Cr (2209-type) filler; keep heat input roughly 0.5–2.5 kJ/mm and interpass <150 °C, no preheat and normally no PWHT.
Can 1.4424 be formed, bent or molded?
Cold forms with roughly twice the press force of 304 and needs extra springback allowance; hot work 1000–1150 °C followed by full solution anneal ~1020–1100 °C and rapid quench.
1.4424 chemical composition (wt %)
Limits by weight percent from the governing specification, written the way the spec states them — a single maximum for impurities, a range for alloying elements, and the base element as balance. Nominal is the typical mid-range value.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Clow-carbon duplex | ≤ 0.03 | 0.02 |
| Sicharacteristic Si addition for SCC resistance | 1.4 – 2 | 1.7 |
| Mn | 1.2 – 2 | 1.6 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.03 | 0.01 |
| Cr | 18 – 19 | 18.5 |
| Ni | 4.25 – 5.25 | 4.8 |
| Mo | 2.5 – 3 | 2.75 |
| N | 0.05 – 0.1 | 0.07 |
| Fe | balance | — |
What surface finishes work on 1.4424?
Not anodisable — pickle and passivate (ASTM A967) or electropolish after fabrication; grind welds and remove heat tint to preserve chloride SCC and pitting resistance.
Surface treatments FabDigit runs on stainless steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Passivation
Organic Coating
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Stainless Steel 1.4424 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- S31500
- EN / DIN / Werkstoff-Nr.
- X2CrNiMoSi18-5-3
- Trade names
- 3RE60
How much does 1.4424 cost?
1.4424 is a premium-cost stainless steel ($$$), cheaper than about 51% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
1.4424 — frequently asked
What is 1.4424 used for?
1.4424 is typically used for pulp and paper digesters, heat exchangers and sulfite liquor equipment. In short: silicon-alloyed legacy duplex; sulfite SCC resistance; largely superseded by 2205.
What is the yield strength of 1.4424?
1.4424 has a typical yield strength of 490 MPa (71.1 ksi) and a tensile strength of 700 MPa (102 ksi) — stronger than 76% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.
Is 1.4424 easy to machine?
Not especially — machinability is rated poor (30/100, worse than 70% of stainless steel grades). Machines like a work-hardening duplex: ~25 % of 1212, use rigid setups, positive-rake coated carbide, heavy positive feeds and generous coolant to stay under the hardened layer.
Can 1.4424 be welded?
Yes — weldability is rated very good (70/100). Weldable by GTAW/GMAW/SAW with overalloyed 22 %Cr (2209-type) filler; keep heat input roughly 0.5–2.5 kJ/mm and interpass <150 °C, no preheat and normally no PWHT.
What surface finishes work on 1.4424?
Not anodisable — pickle and passivate (ASTM A967) or electropolish after fabrication; grind welds and remove heat tint to preserve chloride SCC and pitting resistance.
Can 1.4424 be formed, bent or molded?
Cold forms with roughly twice the press force of 304 and needs extra springback allowance; hot work 1000–1150 °C followed by full solution anneal ~1020–1100 °C and rapid quench.
What is the maximum service temperature of 1.4424?
1.4424 is rated for continuous use to about 280°C (536 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1.4424 SA-CR and 1.4424-CD?
SA-CR is the default condition — default stocked condition for sheet and strip: solution annealed ~1020–1100 °C, water quenched, cold-rolled 2B finish for vessels and heat-exchanger fabrication. CD: pick when higher yield strength and tighter dimensional tolerance are needed on bar or small-bore tube; ductility and impact energy drop. Yield strength is 490 MPa in SA-CR versus 650 MPa in CD.
How much does 1.4424 cost?
1.4424 is a premium-cost stainless steel ($$$), cheaper than about 51% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- EN 10088-1/-2/-3 Stainless steels — X2CrNiMoSi18-5-3 (1.4424) — CEN (2014)
- ASTM A240 / A789 / A790 (UNS S31500) — ASTM International (2022)
- Sandvik 3RE60 (SAF 2304/duplex family) tube and pipe datasheet — Sandvik Materials Technology (2019)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- Practical Guidelines for the Fabrication of Duplex Stainless Steels — IMOA (2014)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.