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Stainless Steel Incoloy 801 Annealed

Temper · default condition

UNS N08801 · ASTM B408

Standard stocked condition for plate, sheet, tube and bar; best ductility, formability and corrosion resistance.

High cost $$$$

Values for the Annealed condition

Other Incoloy 801 tempers and conditions

Incoloy 801 is listed in 5 conditions; see the grade overview at Incoloy 801.

Compare all 5 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
Solution Annealed
Chosen when maximum creep-rupture life and grain coarsening for high-temperature service are wanted, at the cost of some room-temperature strength.21555045140 HB1.7 % IACS
AnnealedDefaultThis page
mill annealed (≈980–1040 °C, air/water cooled)
Standard stocked condition for plate, sheet, tube and bar; best ductility, formability and corrosion resistance.24058542150 HB—
Stabilize Annealed / Aged
Use where long-term service near 500–700 °C or resistance to intergranular attack after welding is critical; TiC precipitation raises creep strength modestly.27562035170 HB1.7 % IACS
cold drawn bar/tube, lightly stress relieved
Pick for closer dimensional tolerance, better surface finish and higher yield strength on small-diameter bar and tube.4506902517 HRC1.7 % IACS
Cold Worked
For springs, thin strip and wire needing maximum room-temperature strength; ductility and weldability are reduced and strength is lost on heating above ~500 °C.750900828 HRC1.6 % IACS

What is Incoloy 801 Annealed?

Incoloy 801 Annealed is Incoloy 801 in the Annealed temper — standard stocked condition for plate, sheet, tube and bar; best ductility, formability and corrosion resistance. Incoloy 801 Annealed has a yield strength of 240 MPa (34.8 ksi) and a tensile strength of 585 MPa (84.8 ksi) — weaker than 96% of stainless steel grades. Elongation at break is 42% and the elastic modulus is 196 GPa (28.4 Msi). Incoloy 801 Annealed has a density of 7.94 g/cm³ (0.287 lb/in³), heavier than 78% of stainless steel grades. It melts at 1,355°C (2,471 °F).

Advantages

  • Forms and bends easily — 70/100, better than 79% of stainless steel grades
  • High service temperature — 815°C (1,499 °F), better than 77% of stainless steel grades

Limitations

  • High embodied carbon — 8 kg CO₂/kg, worse than 99% of stainless steel grades
  • Poor heat conductor — 11.5 W/m·K (6.64 BTU/hr·ft·°F), worse than 97% of stainless steel grades
  • Low strength — 240 MPa (34.8 ksi), worse than 96% of stainless steel grades
  • Low electrical conductivity — 1.7 % IACS, worse than 93% of stainless steel grades

Incoloy 801 Annealed properties

Typical room-temperature values for Incoloy 801 Annealed; 11 are specific to this condition. Other listed values are Incoloy 801 reference data and may not represent this condition. Bars are the position among stainless steel grades.

Physical3

Incoloy 801 Annealed has a density of 7.94 g/cm³ (0.287 lb/in³), heavier than 78% of stainless steel grades. It melts at 1,355°C (2,471 °F).

Density7.94 g/cm³0.29 lb/in³
Melting Point (Solidus)1,355°C2,471 °F
Liquidus Temperature1,385°C2,525 °F

Mechanical13

Incoloy 801 Annealed has a yield strength of 240 MPa (34.8 ksi) and a tensile strength of 585 MPa (84.8 ksi) — weaker than 96% of stainless steel grades. Elongation at break is 42% and the elastic modulus is 196 GPa (28.4 Msi).

Elastic (Young's) Modulus196 GPa28.4 Msi
Shear Modulus76 GPa11 Msi
Bulk Modulus160 GPa23.2 Msi
Poisson's Ratio0.31
Tensile Strength (Ultimate)585 MPa84.8 ksi
Yield Strength (0.2% offset)240 MPa34.8 ksi
Elongation at Break42%
Reduction in Area55%
Shear Strength400 MPa58 ksi
Fatigue Strength (Endurance Limit)250 MPa36.3 ksi
Charpy V-Notch Impact (RT)150 J111 ft·lbf
Hardness, Brinell150 HB
Hardness, Rockwell B80 HRB

Thermal5

Incoloy 801 Annealed is rated for continuous service to 815°C (1,499 °F). It conducts heat at 11.5 W/m·K (6.64 BTU/hr·ft·°F), worse than 97% of stainless steel grades. Thermal expansion is 14.4 µm/m·K (8 µin/in·°F).

Thermal Conductivity11.5 W/m·K6.6 BTU/hr·ft·°F
Specific Heat Capacity460 J/kg·K0.11 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)14.4 µm/m·K8 µin/in·°F
Max Service Temperature (continuous)815°C1,499 °F
Min Service Temperature-196°C-321 °F

Electrical3

Incoloy 801 Annealed conducts electricity at 1.7 % IACS, worse than 93% of stainless steel grades.

Electrical Conductivity1.7 % IACS
Electrical Resistivity1×10⁻⁶ Ω·m39.4 µΩ·in
Magnetic Responsenon-magnetic in annealed condition (fully austenitic; permeability ≈1.01, may rise slightly after heavy cold work)

Chemical & Environmental3

Corrosion resistance is good (66/100), better than 59% of stainless steel grades.

Galvanic Potential (seawater, vs SCE)-0.15 V
Corrosion ResistanceGood66/100
Chemical Resistance SummaryGood resistance to oxidising and mildly reducing acids, steam, caustics and high-temperature oxidation/carburisation; Ti stabilisation gives strong resistance to sensitisation and chloride SCC; attacked by hot concentrated HCl/HF and by sulphidising (high-sulphur) gases above ~600 °C.

Sustainability4

Producing a kilogram of Incoloy 801 Annealed takes about 110 MJ of energy and emits 8 kg of CO₂ — more than 99% of stainless steel grades. Typical recycled content is 45%.

Embodied Energy (primary production)110 MJ/kg47,292 BTU/lb
Embodied Carbon (primary production)8 kg CO₂/kg
Embodied Water220 L/kg26.4 gal/lb
Typical Recycled Content45%

Manufacturability8

Incoloy 801 Annealed's machinability is poor (30/100, worse than 70% of stainless steel grades); weldability very good (70/100); formability very good (70/100).

MachinabilityPoor30/100
Machinability Rating (AISI 1212 = 100 %)30%
WeldabilityVery good70/100
Formability (cold)Very good70/100
CastabilityFair35/100
Brazeability / SolderabilityGood65/100
PolishabilityVery good70/100
Anodizing Responsen/a — not an anodisable alloy; use pickling/passivation or electropolishing instead

Common Calculations5

Specific Strength (UTS / density)calculated74 kN·m/kg
Specific Stiffness (E / density)calculated24.7 MN·m/kg
Modulus of Resiliencecalculated147 kJ/m³
Thermal Diffusivitycalculated3.1 mm²/s
Thermal Shock Resistance Indexcalculated2

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

Working with Incoloy 801 Annealed

Is Incoloy 801 easy to machine?

Machine like an austenitic Fe-Ni-Cr alloy: rigid setup, positive-rake sharp carbide, slow speed with heavy positive feed, generous flood coolant to beat work hardening and gummy chips.

Can Incoloy 801 be welded?

Readily GTAW/GMAW/SMAW welded with Ni-Cr-Fe (ERNiCr-3 / ENiCrFe-3) or matching filler; keep heat input and interpass temperature low, avoid sulphur/lead contamination, no post-weld heat treatment normally needed thanks to Ti stabilisation.

Can Incoloy 801 be formed, bent or molded?

Good cold formability but high work-hardening rate — allow extra forming loads, intermediate anneals at 980–1040 °C for severe draws; hot work between about 900 and 1200 °C.

What surface finishes work on Incoloy 801?

Pickle/passivate or electropolish after hot work to remove Ti-rich oxide scale; takes a good mechanical polish; not anodisable, and paint/plating are rarely used.

Incoloy 801 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
Ni30 – 3432
Cr19 – 2220.5
Ticarbide stabiliser, key difference vs Alloy 8000.75 – 1.51.1
C≤ 0.10.05
Mn≤ 1.50.8
Si≤ 10.5
Cu≤ 0.50.2
S≤ 0.020.01
Febalance, 39.5 % min per ASTM B408≥ 39.5 (balance)—

Incoloy 801 Annealed — frequently asked

What is Incoloy 801 Annealed used for?

Incoloy 801 Annealed is typically used for gas turbine and furnace hardware, heat-treating fixtures, high-temperature fasteners and process industry tubing. In short: ti-stabilized Alloy 800 variant; higher creep strength than 800; service to 815 °C.

What is the yield strength of Incoloy 801 Annealed?

Incoloy 801 Annealed has a typical yield strength of 240 MPa (34.8 ksi) and a tensile strength of 585 MPa (84.8 ksi) — weaker than 96% of stainless steel grades. Strength varies by condition: see the 5 listed tempers.

Is Incoloy 801 Annealed easy to machine?

Not especially — machinability is rated poor (30/100, worse than 70% of stainless steel grades). Machine like an austenitic Fe-Ni-Cr alloy: rigid setup, positive-rake sharp carbide, slow speed with heavy positive feed, generous flood coolant to beat work hardening and gummy chips.

Can Incoloy 801 Annealed be welded?

Yes — weldability is rated very good (70/100). Readily GTAW/GMAW/SMAW welded with Ni-Cr-Fe (ERNiCr-3 / ENiCrFe-3) or matching filler; keep heat input and interpass temperature low, avoid sulphur/lead contamination, no post-weld heat treatment normally needed thanks to Ti stabilisation.

What surface finishes work on Incoloy 801 Annealed?

Pickle/passivate or electropolish after hot work to remove Ti-rich oxide scale; takes a good mechanical polish; not anodisable, and paint/plating are rarely used.

Can Incoloy 801 Annealed be formed, bent or molded?

Good cold formability but high work-hardening rate — allow extra forming loads, intermediate anneals at 980–1040 °C for severe draws; hot work between about 900 and 1200 °C.

What is the maximum service temperature of Incoloy 801 Annealed?

Incoloy 801 Annealed is rated for continuous use to about 815°C (1,499 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

What is the difference between Incoloy 801 Annealed and Incoloy 801 CW-Hard?

Annealed is the default condition — standard stocked condition for plate, sheet, tube and bar; best ductility, formability and corrosion resistance. CW-Hard: for springs, thin strip and wire needing maximum room-temperature strength; ductility and weldability are reduced and strength is lost on heating above ~500 °C. Yield strength is 240 MPa in Annealed versus 750 MPa in CW-Hard.

Sources

  1. ASTM B408 — Ni-Fe-Cr Alloy Rod and Bar (UNS N08800/N08801/N08810/N08811) — ASTM International (2019)
  2. ASTM B409 — Ni-Fe-Cr Alloy Plate, Sheet and Strip — ASTM International (2021)
  3. ASTM B407 — Ni-Fe-Cr Alloy Seamless Pipe and Tube — ASTM International (2019)
  4. ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
  5. INCOLOY alloy 800 / 800H / 800HT and 801 technical bulletins — Special Metals Corporation (2004)
  6. ASME BPVC Section II Part D allowable stresses, N08801 — ASME (2023)

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.