Stainless Steel 1.4477
EN 1.4477 · UNS S32906 · also Safurex
EN 1.4477 (S32906, X2CrNiMoN29-7-2, Safurex) is a high-chromium 29Cr-7Ni-2Mo super duplex stainless developed for resistance to stress corrosion cracking in carbamate-bearing urea plant environments.
Reference datasheet — 1.4477 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 HR+A condition
1.4477 tempers and conditions
1.4477 is supplied in 4 conditions, soft to hard. HR+A 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 |
|---|---|---|---|---|---|---|
As-welded deposit | Property level to assume for weldments made with controlled heat input when solution annealing after welding is not possible. | 660 | 850 | 22 | 29 HRC | 2 % IACS |
HR+ADefault Hot Rolled + Solution Annealed and Quenched | Standard supply condition for plate and hot-finished products used in urea strippers, reactors and pressure vessels. | 700 | 880 | 30 | 27 HRC | — |
Cold Rolled + Solution Annealed, pickled | Choose for thin sheet, strip and lining plate where a smooth 2B surface and tight thickness tolerance are needed. | 720 | 900 | 30 | 28 HRC | — |
Cold drawn | Higher-strength small-diameter bar and wire for fasteners and springs; lower ductility and reduced SCC margin vs annealed. | 830 | 980 | 20 | 32 HRC | 2 % IACS |
Supply forms, finishes and certifications
Ways 1.4477 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-BAR | Solution Annealed hot-finished / forged bar | Supply form |
SMLS+A | Seamless tube/pipe, solution annealed and pickled | Supply form |
What is 1.4477?
EN 1.4477 (S32906, X2CrNiMoN29-7-2, Safurex) is a high-chromium 29Cr-7Ni-2Mo super duplex stainless developed for resistance to stress corrosion cracking in carbamate-bearing urea plant environments. It is specified where 700 MPa yield, 880 MPa tensile, 30% elongation, 270 HB / 27 HRC and a corrosion score of 88 are required in high-pressure equipment, and is supplied as hot- and cold-rolled annealed plate and sheet, solution-annealed and cold-drawn bar and seamless tube. Service is limited to about 300 °C, machinability is the lowest in the family (25) and weldability is moderate (65), so phase balance must be controlled. Outside urea service, 1.4501 or 1.4507 are the usual alternatives. 1.4477 has a density of 7.8 g/cm³ (0.282 lb/in³), heavier than 50% of stainless steel grades. It melts at 1,350°C (2,462 °F). 1.4477 has a yield strength of 700 MPa (102 ksi) and a tensile strength of 880 MPa (128 ksi) — stronger than 92% of stainless steel grades. Elongation at break is 30% and the elastic modulus is 200 GPa (29 Msi).
What is 1.4477 used for?
- urea reactor components
- fertilizer plant equipment
- high-pressure vessels
Advantages
- Good corrosion resistance — 88/100, better than 97% of stainless steel grades
- High strength — 700 MPa (102 ksi), better than 92% of stainless steel grades
Limitations
- Limited service temperature — 300°C (572 °F), worse than 90% of stainless steel grades
- Difficult to machine — 25/100, worse than 88% of stainless steel grades
- Low electrical conductivity — 2 % IACS, worse than 77% of stainless steel grades
1.4477 properties
Typical room-temperature values for 1.4477-HR+A; bars are the position among stainless steel grades.
Physical3
1.4477 has a density of 7.8 g/cm³ (0.282 lb/in³), heavier than 50% of stainless steel grades. It melts at 1,350°C (2,462 °F).
Mechanical16
1.4477 has a yield strength of 700 MPa (102 ksi) and a tensile strength of 880 MPa (128 ksi) — stronger than 92% of stainless steel grades. Elongation at break is 30% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
1.4477 is rated for continuous service to 300°C (572 °F). It conducts heat at 15 W/m·K (8.67 BTU/hr·ft·°F), worse than 59% of stainless steel grades. Thermal expansion is 12.5 µm/m·K (6.94 µin/in·°F).
Electrical3
1.4477 conducts electricity at 2 % IACS, worse than 77% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is excellent (88/100), better than 97% of stainless steel grades.
Sustainability4
Producing a kilogram of 1.4477 takes about 62 MJ of energy and emits 4.6 kg of CO₂ — more than 75% of stainless steel grades. Typical recycled content is 55%.
Manufacturability7
1.4477's machinability is poor (25/100, worse than 88% of stainless steel grades); weldability good (65/100); formability fair (45/100).
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. 1.4477 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 1.4477
Is 1.4477 easy to machine?
Tough and work-hardening — use rigid setups, positive-rake carbide, heavy constant feed, low-to-moderate speed and flood coolant; expect roughly one fifth of the removal rate of 1212 steel.
Can 1.4477 be welded?
Weldable by GTAW/GMAW/SMAW with matching or over-alloyed super-duplex filler and nitrogen-bearing shielding; keep heat input ~0.5–1.5 kJ/mm and interpass <100 °C to hold 45–55 % ferrite and avoid intermetallics, and solution anneal + quench where the code allows.
Can 1.4477 be formed, bent or molded?
Cold forming needs about twice the force and generous springback allowance versus 304; hot form at 1000–1150 °C followed by full solution anneal at ~1080 °C and rapid water quench.
1.4477 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 to avoid carbide precipitation | ≤ 0.03 | 0.02 |
| Si | ≤ 0.5 | 0.3 |
| Mn | 0.8 – 1.5 | 1.1 |
| P | ≤ 0.03 | — |
| Susually held ≤0.005 for hot workability | ≤ 0.03 | — |
| Cr | 28 – 30 | 29 |
| Ni | 5.8 – 7.5 | 6.6 |
| Mo | 1.5 – 2.6 | 2.1 |
| Naustenite stabiliser, raises PREN | 0.3 – 0.4 | 0.35 |
| Cu | ≤ 0.8 | 0.3 |
| Fe | balance | — |
What surface finishes work on 1.4477?
Pickle in HNO₃/HF or bead-blast plus passivate after hot work; electropolishing is common for urea-service surfaces — no anodizing.
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 1.4477 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
How much does 1.4477 cost?
1.4477 is a high-cost stainless steel ($$$$), pricier than about 78% 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.
1.4477 — frequently asked
What is 1.4477 used for?
1.4477 is typically used for urea reactor components, fertilizer plant equipment and high-pressure vessels. In short: urea-service super duplex; highest yield in family; hardest duplex to machine.
What is the yield strength of 1.4477?
1.4477 has a typical yield strength of 700 MPa (102 ksi) and a tensile strength of 880 MPa (128 ksi) — stronger than 92% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.
Is 1.4477 easy to machine?
Not especially — machinability is rated poor (25/100, worse than 88% of stainless steel grades). Tough and work-hardening — use rigid setups, positive-rake carbide, heavy constant feed, low-to-moderate speed and flood coolant; expect roughly one fifth of the removal rate of 1212 steel.
Can 1.4477 be welded?
Yes — weldability is rated good (65/100). Weldable by GTAW/GMAW/SMAW with matching or over-alloyed super-duplex filler and nitrogen-bearing shielding; keep heat input ~0.5–1.5 kJ/mm and interpass <100 °C to hold 45–55 % ferrite and avoid intermetallics, and solution anneal + quench where the code allows.
What surface finishes work on 1.4477?
Pickle in HNO₃/HF or bead-blast plus passivate after hot work; electropolishing is common for urea-service surfaces — no anodizing.
Can 1.4477 be formed, bent or molded?
Cold forming needs about twice the force and generous springback allowance versus 304; hot form at 1000–1150 °C followed by full solution anneal at ~1080 °C and rapid water quench.
What is the maximum service temperature of 1.4477?
1.4477 is rated for continuous use to about 300°C (572 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 1.4477 HR+A and 1.4477-CD?
HR+A is the default condition — standard supply condition for plate and hot-finished products used in urea strippers, reactors and pressure vessels. CD: higher-strength small-diameter bar and wire for fasteners and springs; lower ductility and reduced SCC margin vs annealed. Yield strength is 700 MPa in HR+A versus 830 MPa in CD.
How much does 1.4477 cost?
1.4477 is a high-cost stainless steel ($$$$), pricier than about 78% 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
- ASTM A240/A240M — Chromium and Chromium-Nickel Stainless Steel Plate, Sheet and Strip (UNS S32906) — ASTM International (2023)
- EN 10088-2/-3 — Stainless steels, technical delivery conditions (1.4477) — CEN (2014)
- Sandvik SAF 2906 / Safurex duplex stainless steel datasheet — Alleima (formerly Sandvik Materials Technology) (2022)
- 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 — International Molybdenum Association (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.