Nickel Alloy Incoloy 800H-CW (Cold worked)
Supply condition
UNS N08810 · EN 1.4958
Use only where higher room-temperature strength/hardness is needed and long-term high-temperature (creep) service is not required.
Values for the CW condition
Other Incoloy 800H tempers and conditions
Incoloy 800H is listed in 6 conditions; see the grade overview at Incoloy 800H.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
SADefault Solution Annealed | Standard supply condition for ASME code high-temperature pressure parts, furnace tubing and plate. | 220 | 520 | 45 | 140 HB | — |
Forged and Annealed | Forged pressure components re-solutioned to restore the coarse ASTM 5 grain size required for creep credit. | 230 | 530 | 42 | 145 HB | 1.7 % IACS |
Hot-Finished and Annealed | Heavy plate, forged/hot-rolled bar and hot-finished tube; slightly higher strength than fully re-solutioned thin product. | 240 | 545 | 42 | 150 HB | 1.7 % IACS |
Cold-Drawn and Annealed | Choose for close-tolerance bright bar and small-diameter tubing that still needs code-annealed properties. | 255 | 560 | 42 | 160 HB | 1.7 % IACS |
As-welded deposit | Typical cross-weld properties of fabricated assemblies welded without post-weld solution treatment. | 300 | 540 | 35 | 165 HB | 1.7 % IACS |
CWThis page Cold worked | Use only where higher room-temperature strength/hardness is needed and long-term high-temperature (creep) service is not required. | 620 | 760 | 15 | 21 HRC | 1.7 % IACS |
What is Incoloy 800H-CW?
Incoloy 800H-CW is Incoloy 800H supplied in the CW condition — use only where higher room-temperature strength/hardness is needed and long-term high-temperature (creep) service is not required. Incoloy 800H-CW has a yield strength of 620 MPa (89.9 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 81% of nickel alloy grades. Elongation at break is 15% and the elastic modulus is 196 GPa (28.4 Msi). Incoloy 800H-CW has a density of 7.94 g/cm³ (0.287 lb/in³), lighter than 88% of nickel alloy grades. It melts at 1,357°C (2,475 °F). SA is the default condition FabDigit quotes; CW is available on request or by drawing note.
Advantages
- Easy to machine — 35/100, better than 97% of nickel alloy grades
- Low embodied carbon — 9 kg CO₂/kg, better than 91% of nickel alloy grades
- Tough — resists crack growth — 130 MPa·√m (118.3 ksi·√in), better than 85% of nickel alloy grades
- High strength — 620 MPa (89.9 ksi), better than 81% of nickel alloy grades
- High electrical conductivity — 1.7 % IACS, better than 79% of nickel alloy grades
Limitations
- Limited ductility — 15%, worse than 81% of nickel alloy grades
Incoloy 800H-CW properties
Typical room-temperature values for Incoloy 800H-CW; 23 are specific to this condition. Other listed values are Incoloy 800H reference data and may not represent this condition. Bars are the position among nickel alloy grades.
Physical3
Incoloy 800H-CW has a density of 7.94 g/cm³ (0.287 lb/in³), lighter than 88% of nickel alloy grades. It melts at 1,357°C (2,475 °F).
Mechanical15
Incoloy 800H-CW has a yield strength of 620 MPa (89.9 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 81% of nickel alloy grades. Elongation at break is 15% and the elastic modulus is 196 GPa (28.4 Msi).
Thermal6
Incoloy 800H-CW is rated for continuous service to 600°C (1,112 °F). It conducts heat at 11.5 W/m·K (6.64 BTU/hr·ft·°F), better than 57% of nickel alloy grades. Thermal expansion is 14.4 µm/m·K (8 µin/in·°F).
Electrical3
Incoloy 800H-CW conducts electricity at 1.7 % IACS, better than 79% of nickel alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (73/100), worse than 66% of nickel alloy grades.
Sustainability4
Producing a kilogram of Incoloy 800H-CW takes about 105 MJ of energy and emits 9 kg of CO₂ — less than 94% of nickel alloy grades. Typical recycled content is 35%.
Manufacturability7
Incoloy 800H-CW's machinability is fair (35/100, better than 97% of nickel alloy grades); weldability very good (70/100); formability fair (35/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Incoloy 800H-CW
Is Incoloy 800H easy to machine?
Gummy and work-hardening — use rigid setups, positive-rake carbide, low speed (15–30 m/min) with heavy positive feed and copious sulphur-free coolant; never dwell in the cut.
Can Incoloy 800H be welded?
Readily welded by GTAW/GMAW/SMAW with ERNiCr-3 or ENiCrFe-2/-3 filler, low heat input, no preheat, interpass <150 °C; keep sulphur/lead contamination off the joint and re-solution treat if full creep credit is required.
Can Incoloy 800H be formed, bent or molded?
Excellent cold formability at ~2× the force of 304; hot work at 1150–900 °C and finish above 900 °C, then solution anneal at 1120–1180 °C and rapid cool to restore the coarse ASTM 5 grain size.
What surface finishes work on Incoloy 800H?
Pickle in HNO3-HF or grit blast plus passivation to remove green Cr-rich scale; not anodisable — protective service comes from the self-forming Cr2O3/spinel layer.
Incoloy 800H 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 – 35 | 32 |
| Cr | 19 – 23 | 21 |
| Ccontrolled carbon — key difference vs Alloy 800 | 0.05 – 0.1 | 0.08 |
| Al | 0.15 – 0.6 | 0.4 |
| Ti | 0.15 – 0.6 | 0.4 |
| Al+Ticombined limit | 0.3 – 1.2 | 0.8 |
| Mn | ≤ 1.5 | 0.8 |
| Si | ≤ 1 | 0.4 |
| Cu | ≤ 0.75 | 0.2 |
| S | ≤ 0.02 | 0 |
| Fe39.5 % min per ASTM B409 | ≥ 39.5 (balance) | — |
Incoloy 800H-CW — frequently asked
What is Incoloy 800H-CW used for?
Incoloy 800H-CW is typically used for reformer/cracker tubes, high-temperature pressure vessels and heat treating fixtures. In short: creep-rated Alloy 800; coarse-grain, controlled carbon; 1100 °C furnace service.
What is the yield strength of Incoloy 800H-CW?
Incoloy 800H-CW has a typical yield strength of 620 MPa (89.9 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 81% of nickel alloy grades. Strength varies by condition: see the 6 listed tempers.
Is Incoloy 800H-CW easy to machine?
Not especially — machinability is rated fair (35/100, better than 97% of nickel alloy grades). Gummy and work-hardening — use rigid setups, positive-rake carbide, low speed (15–30 m/min) with heavy positive feed and copious sulphur-free coolant; never dwell in the cut.
Can Incoloy 800H-CW be welded?
Yes — weldability is rated very good (70/100). Readily welded by GTAW/GMAW/SMAW with ERNiCr-3 or ENiCrFe-2/-3 filler, low heat input, no preheat, interpass <150 °C; keep sulphur/lead contamination off the joint and re-solution treat if full creep credit is required.
What surface finishes work on Incoloy 800H-CW?
Pickle in HNO3-HF or grit blast plus passivation to remove green Cr-rich scale; not anodisable — protective service comes from the self-forming Cr2O3/spinel layer.
Can Incoloy 800H-CW be formed, bent or molded?
Excellent cold formability at ~2× the force of 304; hot work at 1150–900 °C and finish above 900 °C, then solution anneal at 1120–1180 °C and rapid cool to restore the coarse ASTM 5 grain size.
What is the maximum service temperature of Incoloy 800H-CW?
Incoloy 800H-CW is rated for continuous use to about 600°C (1,112 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Incoloy 800H-SA and Incoloy 800H-CW?
SA is the default condition — standard supply condition for ASME code high-temperature pressure parts, furnace tubing and plate. CW: use only where higher room-temperature strength/hardness is needed and long-term high-temperature (creep) service is not required. Yield strength is 220 MPa in SA versus 620 MPa in CW.
Sources
- ASTM B409 — Ni-Fe-Cr Alloy Plate, Sheet and Strip (UNS N08810) — ASTM International (2021)
- ASTM B407 / B408 / B564 — Ni-Fe-Cr Alloy Seamless Pipe & Tube, Rod & Bar, Forgings — ASTM International (2019)
- ASME BPVC Section II Part D — Allowable stresses, SB-409/SB-407 N08810 — ASME (2023)
- INCOLOY alloys 800H & 800HT — publication SMC-047 — Special Metals Corporation (2004)
- VDM Alloy 800 H / 800 HT material data sheet No. 4029 — VDM Metals (2018)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
- EN 10095 / W.Nr. 1.4958 heat-resisting steels and nickel alloys — CEN (1999)
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.