FabDigitFabDigit

Nickel Alloy Alloy 31 AsWelded

Other

UNS N08031 · EN 1.4562 · also Nicrofer 3127hMo

Joint condition of welded pipe and fabrications; use over-alloyed Ni-Cr-Mo filler to restore pitting resistance.

High cost $$$$

Values for the AsWelded condition

Other Alloy 31 tempers and conditions

Alloy 31 is listed in 4 conditions; see the grade overview at Alloy 31.

Compare all 4 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
AnnealedDefault
Solution Annealed (approx. 1150–1180 °C, water quenched)
Standard supply condition for plate, sheet, tube and forgings — maximum corrosion resistance and ductility.34070050180 HB—
Cold Drawn + Solution Annealed (seamless tube, bar)
Seamless tubing and bright bar delivered in the annealed condition for acid service heat exchangers.35070048185 HB1.7 % IACS
AsWeldedThis page
As-Welded (autogenous / matching over-alloyed filler weld metal)
Joint condition of welded pipe and fabrications; use over-alloyed Ni-Cr-Mo filler to restore pitting resistance.38068035200 HB1.7 % IACS
Cold Worked / Strain Hardened (as-drawn, not re-annealed)
Higher-strength bar, wire and small tube where corrosion service is mild and stiffness/strength matter.7009002227 HRC1.7 % IACS

What is Alloy 31 AsWelded?

Alloy 31 AsWelded is Alloy 31 in the AsWelded condition — joint condition of welded pipe and fabrications; use over-alloyed Ni-Cr-Mo filler to restore pitting resistance. Alloy 31 AsWelded has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 680 MPa (98.6 ksi) — weaker than 53% of nickel alloy grades. Elongation at break is 35% and the elastic modulus is 195 GPa (28.3 Msi). Alloy 31 AsWelded has a density of 8.02 g/cm³ (0.29 lb/in³), lighter than 84% of nickel alloy grades. It melts at 1,320°C (2,408 °F). Annealed is the default condition FabDigit quotes; AsWelded is available on request or by drawing note.

Advantages

  • Low embodied carbon — 7.5 kg CO₂/kg, better than 96% of nickel alloy grades
  • High electrical conductivity — 1.7 % IACS, better than 76% of nickel alloy grades

Limitations

  • Limited service temperature — 400°C (752 °F), worse than 94% of nickel alloy grades

Alloy 31 AsWelded properties

Typical room-temperature values for Alloy 31 AsWelded; 20 are specific to this condition. Other listed values are Alloy 31 reference data and may not represent this condition. Bars are the position among nickel alloy grades.

Physical3

Alloy 31 AsWelded has a density of 8.02 g/cm³ (0.29 lb/in³), lighter than 84% of nickel alloy grades. It melts at 1,320°C (2,408 °F).

Density8.02 g/cm³0.29 lb/in³
Melting Point (Solidus)1,320°C2,408 °F
Liquidus Temperature1,360°C2,480 °F

Mechanical14

Alloy 31 AsWelded has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 680 MPa (98.6 ksi) — weaker than 53% of nickel alloy grades. Elongation at break is 35% and the elastic modulus is 195 GPa (28.3 Msi).

Elastic (Young's) Modulus195 GPa28.3 Msi
Shear Modulus75 GPa10.9 Msi
Bulk Modulus163 GPa23.6 Msi
Poisson's Ratio0.3
Tensile Strength (Ultimate)680 MPa98.6 ksi
Yield Strength (0.2% offset)380 MPa55.1 ksi
Elongation at Break35%
Reduction in Area45%
Shear Strength455 MPa66 ksi
Fatigue Strength (Endurance Limit)210 MPa30.5 ksi
Charpy V-Notch Impact (RT)110 J81.1 ft·lbf
Hardness, Brinell200 HB
Hardness, Rockwell B93 HRB
Hardness, Vickers210 HV

Thermal6

Alloy 31 AsWelded is rated for continuous service to 400°C (752 °F). It conducts heat at 11 W/m·K (6.36 BTU/hr·ft·°F), worse than 60% of nickel alloy grades. Thermal expansion is 14.5 µm/m·K (8.06 µin/in·°F).

Thermal Conductivity11 W/m·K6.4 BTU/hr·ft·°F
Specific Heat Capacity450 J/kg·K0.11 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)14.5 µm/m·K8.1 µin/in·°F
Latent Heat of Fusion285 J/g123 BTU/lb
Max Service Temperature (continuous)400°C752 °F
Min Service Temperature-196°C-321 °F

Electrical3

Alloy 31 AsWelded conducts electricity at 1.7 % IACS, better than 76% of nickel alloy grades.

Electrical Conductivity1.7 % IACS
Electrical Resistivity1×10⁻⁶ Ω·m39.4 µΩ·in
Magnetic Responsenon-magnetic

Chemical & Environmental3

Corrosion resistance is excellent (85/100), better than 74% of nickel alloy grades.

Galvanic Potential (seawater, vs SCE)-0.05 V
Corrosion ResistanceExcellent85/100
Chemical Resistance SummaryOutstanding in hot sulfuric acid across a wide concentration range, in wet-process phosphoric acid and in chloride-bearing brines/seawater; CPT typically >70 °C. Good in caustics and organic acids; not for reducing hydrochloric acid at high concentration, nor for hot oxidizing halide media such as wet chlorine.

Sustainability4

Producing a kilogram of Alloy 31 AsWelded takes about 95 MJ of energy and emits 7.5 kg of CO₂ — less than 97% of nickel alloy grades. Typical recycled content is 35%.

Embodied Energy (primary production)95 MJ/kg40,843 BTU/lb
Embodied Carbon (primary production)7.5 kg CO₂/kg
Embodied Water300 L/kg35.9 gal/lb
Typical Recycled Content35%

Manufacturability7

Alloy 31 AsWelded's machinability is poor (18/100, worse than 61% of nickel alloy grades); weldability very good (70/100); formability fair (45/100).

MachinabilityPoor18/100
Machinability Rating (AISI 1212 = 100 %)12%
WeldabilityVery good70/100
Formability (cold)Fair45/100
CastabilityFair35/100
Brazeability / SolderabilityFair45/100
PolishabilityVery good78/100

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with Alloy 31 AsWelded

Is Alloy 31 easy to machine?

Very gummy and strongly work-hardening — use rigid setups, sharp positive-rake carbide, low speed (20–35 m/min) with heavy positive feed and copious flood coolant; avoid dwelling.

Can Alloy 31 be welded?

Weld with GTAW/GMAW/SMAW using over-alloyed Ni-Cr-Mo filler (e.g. ERNiCrMo-3/-4 type), low heat input, interpass <150 °C, no preheat and no PWHT required.

Can Alloy 31 be formed, bent or molded?

Cold forms readily but needs roughly twice the force of 304; hot work 1150–900 °C and always solution anneal + quench after hot forming or heavy cold work.

What surface finishes work on Alloy 31?

Pickle and passivate after welding to remove heat tint (essential for full pitting resistance); polishes to a bright mirror finish, no anodizing applicable.

Alloy 31 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.

ElementSpec limit (wt %)Nominal
Clow carbon for intergranular corrosion resistance≤ 0.020.01
Si≤ 0.30.2
Mn≤ 21.5
P≤ 0.02—
S≤ 0.01—
Cr26 – 2827
Ni30 – 3231
Mo6 – 76.5
Cuimproves sulfuric acid resistance1 – 1.41.2
Nraises PREN and strength0.15 – 0.250.2
Febalance, approx. 31–33 %balance—

Alloy 31 AsWelded — frequently asked

What is Alloy 31 AsWelded used for?

Alloy 31 AsWelded is typically used for acid production plants, flue gas desulfurization, phosphoric acid evaporators and heat exchangers. In short: super-austenitic acid grade; high chloride pitting resistance; hardest of the family to machine.

What is the yield strength of Alloy 31 AsWelded?

Alloy 31 AsWelded has a typical yield strength of 380 MPa (55.1 ksi) and a tensile strength of 680 MPa (98.6 ksi) — weaker than 53% of nickel alloy grades. Strength varies by condition: see the 4 listed tempers.

Is Alloy 31 AsWelded easy to machine?

Not especially — machinability is rated poor (18/100, worse than 61% of nickel alloy grades). Very gummy and strongly work-hardening — use rigid setups, sharp positive-rake carbide, low speed (20–35 m/min) with heavy positive feed and copious flood coolant; avoid dwelling.

Can Alloy 31 AsWelded be welded?

Yes — weldability is rated very good (70/100). Weld with GTAW/GMAW/SMAW using over-alloyed Ni-Cr-Mo filler (e.g. ERNiCrMo-3/-4 type), low heat input, interpass <150 °C, no preheat and no PWHT required.

What surface finishes work on Alloy 31 AsWelded?

Pickle and passivate after welding to remove heat tint (essential for full pitting resistance); polishes to a bright mirror finish, no anodizing applicable.

Can Alloy 31 AsWelded be formed, bent or molded?

Cold forms readily but needs roughly twice the force of 304; hot work 1150–900 °C and always solution anneal + quench after hot forming or heavy cold work.

What is the maximum service temperature of Alloy 31 AsWelded?

Alloy 31 AsWelded is rated for continuous use to about 400°C (752 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

Sources

  1. ASTM B625 — UNS N08031 plate, sheet and strip — ASTM International (2022)
  2. EN 10088-2 / material 1.4562 (X1NiCrMoCu32-28-7) — CEN (2014)
  3. Nicrofer 3127 hMo — Alloy 31 material data sheet — VDM Metals (2020)
  4. Super-austenitic stainless steels — corrosion and physical data — Outokumpu (2021)
  5. ASM Handbook Vol. 13B — Corrosion: Materials — ASM International (2005)

Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.