Stainless Steel Incoloy 801 CW-Hard
Supply condition
UNS N08801 · ASTM B408
CW-Hard = 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.
Values for the CW-Hard 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 datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
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. | 215 | 550 | 45 | 140 HB | 1.7 % IACS |
AnnealedDefault mill annealed (≈980–1040 °C, air/water cooled) | Standard stocked condition for plate, sheet, tube and bar; best ductility, formability and corrosion resistance. | 240 | 585 | 42 | 150 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. | 275 | 620 | 35 | 170 HB | 1.7 % 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. | 450 | 690 | 25 | 17 HRC | 1.7 % IACS |
CW-HardThis page 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. | 750 | 900 | 8 | 28 HRC | 1.6 % IACS |
What is Incoloy 801 CW-Hard?
Incoloy 801 CW-Hard is Incoloy 801 supplied in the CW-Hard condition — 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. Incoloy 801 CW-Hard has a yield strength of 750 MPa (109 ksi) and a tensile strength of 900 MPa (131 ksi) — stronger than 93% of stainless steel grades. Elongation at break is 8% and the elastic modulus is 200 GPa (29 Msi). Incoloy 801 CW-Hard 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). Annealed is the default condition FabDigit quotes; CW-Hard is available on request or by drawing note.
Advantages
- High strength — 750 MPa (109 ksi), better than 93% of stainless steel grades
Limitations
- Limited ductility — 8%, worse than 99% of stainless steel grades
- Low electrical conductivity — 1.6 % IACS, worse than 99% of stainless steel grades
- 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
- Difficult to machine — 25/100, worse than 88% of stainless steel grades
Incoloy 801 CW-Hard properties
Typical room-temperature values for Incoloy 801 CW-Hard; 24 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 CW-Hard 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).
Mechanical13
Incoloy 801 CW-Hard has a yield strength of 750 MPa (109 ksi) and a tensile strength of 900 MPa (131 ksi) — stronger than 93% of stainless steel grades. Elongation at break is 8% and the elastic modulus is 200 GPa (29 Msi).
Thermal5
Incoloy 801 CW-Hard is rated for continuous service to 480°C (896 °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).
Electrical3
Incoloy 801 CW-Hard conducts electricity at 1.6 % IACS, worse than 99% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (62/100), worse than 52% of stainless steel grades.
Sustainability4
Producing a kilogram of Incoloy 801 CW-Hard takes about 110 MJ of energy and emits 8 kg of CO₂ — more than 99% of stainless steel grades. Typical recycled content is 45%.
Manufacturability8
Incoloy 801 CW-Hard's machinability is poor (25/100, worse than 88% of stainless steel grades); weldability good (55/100); formability poor (25/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Incoloy 801 CW-Hard
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.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| Ni | 30 – 34 | 32 |
| Cr | 19 – 22 | 20.5 |
| Ticarbide stabiliser, key difference vs Alloy 800 | 0.75 – 1.5 | 1.1 |
| C | ≤ 0.1 | 0.05 |
| Mn | ≤ 1.5 | 0.8 |
| Si | ≤ 1 | 0.5 |
| Cu | ≤ 0.5 | 0.2 |
| S | ≤ 0.02 | 0.01 |
| Febalance, 39.5 % min per ASTM B408 | ≥ 39.5 (balance) | — |
Incoloy 801 CW-Hard — frequently asked
What is Incoloy 801 CW-Hard used for?
Incoloy 801 CW-Hard 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 CW-Hard?
Incoloy 801 CW-Hard has a typical yield strength of 750 MPa (109 ksi) and a tensile strength of 900 MPa (131 ksi) — stronger than 93% of stainless steel grades. Strength varies by condition: see the 5 listed tempers.
Is Incoloy 801 CW-Hard easy to machine?
Not especially — machinability is rated poor (25/100, worse than 88% 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 CW-Hard be welded?
Yes — weldability is rated good (55/100). 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 CW-Hard?
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 CW-Hard 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 CW-Hard?
Incoloy 801 CW-Hard is rated for continuous use to about 480°C (896 °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
- ASTM B408 — Ni-Fe-Cr Alloy Rod and Bar (UNS N08800/N08801/N08810/N08811) — ASTM International (2019)
- ASTM B409 — Ni-Fe-Cr Alloy Plate, Sheet and Strip — ASTM International (2021)
- ASTM B407 — Ni-Fe-Cr Alloy Seamless Pipe and Tube — ASTM International (2019)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
- INCOLOY alloy 800 / 800H / 800HT and 801 technical bulletins — Special Metals Corporation (2004)
- 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.