Stainless Steel N08366 Annealed
Temper · default condition
UNS N08366 · ASTM B676/B677
Standard stocked condition for plate, sheet, pipe and tube; maximum corrosion resistance and ductility.
Values for the Annealed condition
Other N08366 tempers and conditions
N08366 is listed in 4 conditions; see the grade overview at N08366.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AnnealedDefaultThis page solution annealed and water quenched (plate/sheet/tube) | Standard stocked condition for plate, sheet, pipe and tube; maximum corrosion resistance and ductility. | 305 | 655 | 45 | 170 HB | — |
As-welded deposit | Reference condition for welded tube and fabrication; expect some Mo segregation unless overalloyed Ni-base filler is used. | 320 | 640 | 35 | 185 HB | 1.7 % IACS |
Cold drawn | Choose for bar and fastener stock needing better straightness, surface finish and higher yield strength. | 480 | 760 | 30 | 19 HRC | 1.7 % IACS |
Quarter hard | Use for springy strip, gaskets and diaphragms where higher yield strength is needed and forming is minimal. | 620 | 860 | 20 | 25 HRC | 1.7 % IACS |
What is N08366 Annealed?
N08366 Annealed is N08366 in the Annealed temper — standard stocked condition for plate, sheet, pipe and tube; maximum corrosion resistance and ductility. N08366 Annealed has a yield strength of 305 MPa (44.2 ksi) and a tensile strength of 655 MPa (95 ksi) — weaker than 66% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 196 GPa (28.4 Msi). N08366 Annealed has a density of 8.08 g/cm³ (0.292 lb/in³), heavier than 99% of stainless steel grades. It melts at 1,320°C (2,408 °F).
Advantages
- Good corrosion resistance — 82/100, better than 90% of stainless steel grades
- Ductile — tolerates forming and impact — 45%, better than 76% of stainless steel grades
Limitations
- Poor heat conductor — 11.5 W/m·K (6.64 BTU/hr·ft·°F), worse than 97% of stainless steel grades
- Difficult to machine — 22/100, worse than 95% of stainless steel grades
- Low electrical conductivity — 1.7 % IACS, worse than 93% of stainless steel grades
- High embodied carbon — 6.5 kg CO₂/kg, worse than 93% of stainless steel grades
N08366 Annealed properties
Typical room-temperature values for N08366 Annealed; 11 are specific to this condition. Other listed values are N08366 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
N08366 Annealed has a density of 8.08 g/cm³ (0.292 lb/in³), heavier than 99% of stainless steel grades. It melts at 1,320°C (2,408 °F).
Mechanical14
N08366 Annealed has a yield strength of 305 MPa (44.2 ksi) and a tensile strength of 655 MPa (95 ksi) — weaker than 66% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 196 GPa (28.4 Msi).
Thermal5
N08366 Annealed is rated for continuous service to 425°C (797 °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 15.3 µm/m·K (8.5 µin/in·°F).
Electrical3
N08366 Annealed conducts electricity at 1.7 % IACS, worse than 93% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is very good (82/100), better than 90% of stainless steel grades.
Sustainability4
Producing a kilogram of N08366 Annealed takes about 80 MJ of energy and emits 6.5 kg of CO₂ — more than 89% of stainless steel grades. Typical recycled content is 45%.
Manufacturability7
N08366 Annealed's machinability is poor (22/100, worse than 95% of stainless steel grades); weldability very good (70/100); formability good (60/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with N08366 Annealed
Is N08366 easy to machine?
Slow speeds, heavy positive-rake carbide tooling, rigid setups and flood coolant; it work-hardens strongly and must be cut, not rubbed (~25 % of 1212).
Can N08366 be welded?
GTAW/GMAW/SMAW with overalloyed Ni-base filler (ERNiCrMo-3/-4) to keep weld Mo up; no preheat, low heat input, interpass below ~150 °C, no post-weld heat treat needed for thin sections.
Can N08366 be formed, bent or molded?
Cold forms well but needs ~1.5–2× the press force of 304 with allowance for springback; hot work 1150–1200 °C followed by rapid cooling to avoid σ/χ phase.
What surface finishes work on N08366?
Pickle in HNO₃-HF and passivate after hot work or welding to restore the passive film; electropolish or mechanically polish for sanitary service — no anodizing.
N08366 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 |
|---|---|---|
| Cmax per ASTM B688 | ≤ 0.04 | 0.02 |
| Mn | ≤ 2 | 1 |
| P | ≤ 0.03 | 0.02 |
| S | ≤ 0.03 | 0.01 |
| Si | ≤ 1 | 0.5 |
| Cr | 20 – 22 | 21 |
| Ni | 23.5 – 25.5 | 24.5 |
| Mosource of pitting/crevice resistance | 6 – 7 | 6.5 |
| Cu | ≤ 0.75 | 0.2 |
| Feremainder, ~46 % | balance | — |
N08366 Annealed — frequently asked
What is N08366 Annealed used for?
N08366 Annealed is typically used for seawater piping, pulp and paper bleach equipment, flue-gas desulfurization components and chemical process tanks. In short: first-generation 6Mo superaustenitic; chloride pitting resistance; AL-6XN predecessor grade.
What is the yield strength of N08366 Annealed?
N08366 Annealed has a typical yield strength of 305 MPa (44.2 ksi) and a tensile strength of 655 MPa (95 ksi) — weaker than 66% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.
Is N08366 Annealed easy to machine?
Not especially — machinability is rated poor (22/100, worse than 95% of stainless steel grades). Slow speeds, heavy positive-rake carbide tooling, rigid setups and flood coolant; it work-hardens strongly and must be cut, not rubbed (~25 % of 1212).
Can N08366 Annealed be welded?
Yes — weldability is rated very good (70/100). GTAW/GMAW/SMAW with overalloyed Ni-base filler (ERNiCrMo-3/-4) to keep weld Mo up; no preheat, low heat input, interpass below ~150 °C, no post-weld heat treat needed for thin sections.
What surface finishes work on N08366 Annealed?
Pickle in HNO₃-HF and passivate after hot work or welding to restore the passive film; electropolish or mechanically polish for sanitary service — no anodizing.
Can N08366 Annealed be formed, bent or molded?
Cold forms well but needs ~1.5–2× the press force of 304 with allowance for springback; hot work 1150–1200 °C followed by rapid cooling to avoid σ/χ phase.
What is the maximum service temperature of N08366 Annealed?
N08366 Annealed is rated for continuous use to about 425°C (797 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between N08366 Annealed and N08366-CD?
Annealed is the default condition — standard stocked condition for plate, sheet, pipe and tube; maximum corrosion resistance and ductility. CD: choose for bar and fastener stock needing better straightness, surface finish and higher yield strength. Yield strength is 305 MPa in Annealed versus 480 MPa in CD.
Sources
- ASTM B688 — Chromium-Nickel-Molybdenum-Iron (UNS N08366/N08367) Plate, Sheet, and Strip — ASTM International (2018)
- ASTM B676 / B677 — Welded and Seamless UNS N08366/N08367 Tube and Pipe — ASTM International (2019)
- ASTM B691 — UNS N08366/N08367 Rod, Bar, and Wire — ASTM International (2016)
- AL-6X / AL-6XN Alloy Technical Data — Allegheny Ludlum / ATI (2010)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- 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.