Stainless Steel N08031
UNS N08031 · EN 1.4562, X1NiCrMoCu32-28-7
N08031 (1.4562, X1NiCrMoCu32-28-7, Alloy 31) is a high Ni-Cr-Mo superaustenitic stainless steel with a copper addition for resistance to hot sulfuric and phosphoric acids, used where 6% Mo austenitics are insufficient.
Reference datasheet — N08031 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 condition
N08031 tempers and conditions
N08031 is supplied in 7 conditions, soft to hard. SA is the default FabDigit quotes; the values on this page are for it.
Compare all 7 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
hot rolled, solution annealed and pickled plate | Heavy plate for vessels, tube sheets and FGD equipment; lowest strength, highest ductility of the annealed forms. | 340 | 690 | 55 | 175 HB | 1.7 % IACS |
Forged + SA | Forgings and heavy fittings per ASTM B564-type practice, solution annealed after hot working to dissolve intermetallics. | 340 | 690 | 50 | 180 HB | 1.7 % IACS |
SADefault Solution annealed | Standard supply condition for all product forms; maximum corrosion resistance and ductility. | 360 | 700 | 50 | 180 HB | — |
cold rolled, bright/2B annealed sheet & strip | Thin sheet and strip for linings, plate heat exchangers and formed parts requiring a smooth surface. | 380 | 720 | 48 | 185 HB | 1.7 % IACS |
As-welded deposit | Property set for as-welded fabrication using over-alloyed filler (e.g. ERNiCrMo-3/-4 or matching 31 filler); no post-weld heat treatment normally applied. | 380 | 680 | 35 | 195 HB | 1.6 % IACS |
Cold drawn | Cold drawn bar for fasteners, shafts and machined valve parts where higher yield strength and close tolerance are needed. | 550 | 800 | 30 | 20 HRC | 1.7 % IACS |
Cold worked | Cold-pilgered or cold-drawn tubing supplied without final anneal where higher pressure rating is required; corrosion performance is best restored by a final solution anneal. | 620 | 850 | 25 | 24 HRC | 1.7 % IACS |
What is N08031?
N08031 (1.4562, X1NiCrMoCu32-28-7, Alloy 31) is a high Ni-Cr-Mo superaustenitic stainless steel with a copper addition for resistance to hot sulfuric and phosphoric acids, used where 6% Mo austenitics are insufficient. It is supplied as solution-annealed plate, sheet, tube, bar and forgings, with typical values of 360 MPa yield, 700 MPa tensile, 50% elongation and 180 HB (88 HRB). Limits are cost, availability, a 450 °C service ceiling and very poor machinability (score 20); welding requires over-alloyed nickel-base filler. S31254 is the usual lower-cost step down. N08031 has a density of 8.02 g/cm³ (0.29 lb/in³), heavier than 97% of stainless steel grades. It melts at 1,320°C (2,408 °F). N08031 has a yield strength of 360 MPa (52.2 ksi) and a tensile strength of 700 MPa (102 ksi) — weaker than 51% of stainless steel grades. Elongation at break is 50% and the elastic modulus is 195 GPa (28.3 Msi).
What is N08031 used for?
- sulfuric acid production
- flue gas desulfurization systems
- phosphoric acid plants
- pulp and paper bleaching equipment
- chemical process piping
Advantages
- Good corrosion resistance — 92/100, better than 99% of stainless steel grades
- Ductile — tolerates forming and impact — 50%, better than 90% of stainless steel grades
Limitations
- Poor heat conductor — 11 W/m·K (6.36 BTU/hr·ft·°F), worse than 99% of stainless steel grades
- High embodied carbon — 8 kg CO₂/kg, worse than 99% of stainless steel grades
- Difficult to machine — 20/100, worse than 98% of stainless steel grades
- Low electrical conductivity — 1.7 % IACS, worse than 93% of stainless steel grades
N08031 properties
Typical room-temperature values for N08031-SA; bars are the position among stainless steel grades.
Physical3
N08031 has a density of 8.02 g/cm³ (0.29 lb/in³), heavier than 97% of stainless steel grades. It melts at 1,320°C (2,408 °F).
Mechanical14
N08031 has a yield strength of 360 MPa (52.2 ksi) and a tensile strength of 700 MPa (102 ksi) — weaker than 51% of stainless steel grades. Elongation at break is 50% and the elastic modulus is 195 GPa (28.3 Msi).
Thermal6
N08031 is rated for continuous service to 450°C (842 °F). It conducts heat at 11 W/m·K (6.36 BTU/hr·ft·°F), worse than 99% of stainless steel grades. Thermal expansion is 14.5 µm/m·K (8.06 µin/in·°F).
Electrical3
N08031 conducts electricity at 1.7 % IACS, worse than 93% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is excellent (92/100), better than 99% of stainless steel grades.
Sustainability4
Producing a kilogram of N08031 takes about 100 MJ of energy and emits 8 kg of CO₂ — more than 98% of stainless steel grades. Typical recycled content is 35%.
Manufacturability7
N08031's machinability is poor (20/100, worse than 98% of stainless steel grades); weldability very good (70/100); formability good (65/100).
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. N08031 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with N08031
Is N08031 easy to machine?
Machine like a nickel alloy: rigid setup, positive-rake carbide, heavy constant feed to cut under the work-hardened layer, low speed (~15–25 m/min) with flood coolant.
Can N08031 be welded?
GTAW/GMAW/SMAW with over-alloyed Ni-base filler (ERNiCrMo-3/-4 or matching alloy 31 filler), low heat input, interpass < 150 °C, no preheat or PWHT; avoid autogenous welding.
Can N08031 be formed, bent or molded?
Excellent cold ductility but ~2× the forming load of 304; hot working 1150–1000 °C followed by mandatory solution anneal and quench.
N08031 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 for intergranular corrosion resistance | ≤ 0.02 | 0.01 |
| Si | ≤ 0.3 | 0.15 |
| Mn | ≤ 2 | 1 |
| P | ≤ 0.02 | 0.02 |
| S | ≤ 0.01 | 0 |
| Cr | 26 – 28 | 27 |
| Ni | 30 – 32 | 31 |
| Mo | 6 – 7 | 6.5 |
| Cukey for hot sulfuric/phosphoric acid resistance | 1 – 1.4 | 1.2 |
| Nraises PREN and strength | 0.15 – 0.25 | 0.2 |
| Febalance, approx. 31–33% | balance |
What surface finishes work on N08031?
Pickle (HNO3-HF) or bead-blast plus passivation after fabrication to remove heat tint; electropolishing gives best performance in acid service; never anodized or plated.
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 N08031 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- EN / DIN / Werkstoff-Nr.
- 1.4562X1NiCrMoCu32-28-71.4563
- Trade names
- Alloy 31Nicrofer 3127hMo
How much does N08031 cost?
N08031 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.
N08031 — frequently asked
What is N08031 used for?
N08031 is typically used for sulfuric acid production, flue gas desulfurization systems, phosphoric acid plants, pulp and paper bleaching equipment and chemical process piping. In short: copper-bearing acid superaustenitic; beyond 6% Mo grades; top corrosion score, poor machinability.
What is the yield strength of N08031?
N08031 has a typical yield strength of 360 MPa (52.2 ksi) and a tensile strength of 700 MPa (102 ksi) — weaker than 51% of stainless steel grades. Strength varies by condition: see the 7 listed tempers.
Is N08031 easy to machine?
Not especially — machinability is rated poor (20/100, worse than 98% of stainless steel grades). Machine like a nickel alloy: rigid setup, positive-rake carbide, heavy constant feed to cut under the work-hardened layer, low speed (~15–25 m/min) with flood coolant.
Can N08031 be welded?
Yes — weldability is rated very good (70/100). GTAW/GMAW/SMAW with over-alloyed Ni-base filler (ERNiCrMo-3/-4 or matching alloy 31 filler), low heat input, interpass < 150 °C, no preheat or PWHT; avoid autogenous welding.
What surface finishes work on N08031?
Pickle (HNO3-HF) or bead-blast plus passivation after fabrication to remove heat tint; electropolishing gives best performance in acid service; never anodized or plated.
Can N08031 be formed, bent or molded?
Excellent cold ductility but ~2× the forming load of 304; hot working 1150–1000 °C followed by mandatory solution anneal and quench.
What is the maximum service temperature of N08031?
N08031 is rated for continuous use to about 450°C (842 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between N08031-SA and N08031-CW?
SA is the default condition — standard supply condition for all product forms; maximum corrosion resistance and ductility. CW: cold-pilgered or cold-drawn tubing supplied without final anneal where higher pressure rating is required; corrosion performance is best restored by a final solution anneal. Yield strength is 360 MPa in SA versus 620 MPa in CW.
How much does N08031 cost?
N08031 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 B625 — Ni-Fe-Cr-Mo-Cu Alloy Plate, Sheet and Strip (UNS N08031) — ASTM International (2021)
- ASTM B622 / B649 — Seamless Pipe & Tube, Bar and Wire for UNS N08031 — ASTM International (2020)
- EN 10088-2 / 10028-7 — Stainless steel 1.4562 (X1NiCrMoCu32-28-7) — CEN (2014)
- Nicrofer 3127 hMo — Alloy 31 material data sheet — VDM Metals (2020)
- ASM Handbook Vol. 13B — Corrosion: Materials (superaustenitic stainless steels) — ASM International (2005)
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.