Steel A182 F92 N+T+PWHT
Heat-treated state
ASTM A182 F92 · UNS K92460
N+T+PWHT = n+T + simulated post-weld heat treatment
Order this when the forging will see field PWHT cycles and design must use post-PWHT (slightly softened) properties.
Values for the N+T+PWHT condition
Other A182 F92 tempers and conditions
A182 F92 is listed in 5 conditions; see the grade overview at A182 F92.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Sub-critical annealed | Interim soft condition for rough machining of large forgings; must be re-normalized/tempered before code service. | 400 | 630 | 26 | 185 HB | 3 % IACS |
N+T+PWHTThis page N+T + simulated post-weld heat treatment | Order this when the forging will see field PWHT cycles and design must use post-PWHT (slightly softened) properties. | 480 | 670 | 24 | 15 HRC | 2.9 % IACS |
N+TDefault Normalized and tempered | Standard ASME/ASTM code condition for F92 flanges, valve bodies and fittings in USC steam service. | 520 | 710 | 22 | 20 HRC | — |
Quenched and tempered | Chosen for heavy-section forgings where still-air normalizing cannot guarantee full martensite through-thickness. | 560 | 745 | 21 | 22 HRC | 2.9 % IACS |
As-forged | Only an intermediate stage — untempered martensite is hard and brittle and is never acceptable for pressure service. | 900 | 1,200 | 10 | 41 HRC | 2.7 % IACS |
What is A182 F92 N+T+PWHT?
A182 F92 N+T+PWHT is A182 F92 heat treated to N+T+PWHT — order this when the forging will see field PWHT cycles and design must use post-PWHT (slightly softened) properties. A182 F92 N+T+PWHT has a yield strength of 480 MPa (69.6 ksi) and a tensile strength of 670 MPa (97.2 ksi) — stronger than 59% of steel grades. Elongation at break is 24% and the elastic modulus is 216 GPa (31.3 Msi). A182 F92 N+T+PWHT has a density of 7.78 g/cm³ (0.281 lb/in³), lighter than 91% of steel grades. It melts at 1,420°C (2,588 °F). N+T is the default condition FabDigit quotes; N+T+PWHT is available on request or by drawing note.
Advantages
- High service temperature — 620°C (1,148 °F), better than 99% of steel grades
- Tough — resists crack growth — 170 MPa·√m (154.7 ksi·√in), better than 98% of steel grades
- Good corrosion resistance — 30/100, better than 95% of steel grades
Limitations
- Low electrical conductivity — 2.9 % IACS, worse than 93% of steel grades
- High embodied carbon — 2.6 kg CO₂/kg, worse than 87% of steel grades
- Poor heat conductor — 27 W/m·K (15.6 BTU/hr·ft·°F), worse than 86% of steel grades
A182 F92 N+T+PWHT properties
Typical room-temperature values for A182 F92 N+T+PWHT; 23 are specific to this condition. Other listed values are A182 F92 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
A182 F92 N+T+PWHT has a density of 7.78 g/cm³ (0.281 lb/in³), lighter than 91% of steel grades. It melts at 1,420°C (2,588 °F).
Mechanical16
A182 F92 N+T+PWHT has a yield strength of 480 MPa (69.6 ksi) and a tensile strength of 670 MPa (97.2 ksi) — stronger than 59% of steel grades. Elongation at break is 24% and the elastic modulus is 216 GPa (31.3 Msi).
Thermal6
A182 F92 N+T+PWHT is rated for continuous service to 620°C (1,148 °F). It conducts heat at 27 W/m·K (15.6 BTU/hr·ft·°F), worse than 86% of steel grades. Thermal expansion is 10.8 µm/m·K (6 µin/in·°F).
Electrical3
A182 F92 N+T+PWHT conducts electricity at 2.9 % IACS, worse than 93% of steel grades.
Chemical & Environmental3
Corrosion resistance is poor (30/100), better than 95% of steel grades.
Sustainability4
Producing a kilogram of A182 F92 N+T+PWHT takes about 34 MJ of energy and emits 2.6 kg of CO₂ — more than 82% of steel grades. Typical recycled content is 30%.
Manufacturability7
A182 F92 N+T+PWHT's machinability is fair (42/100, worse than 73% of steel grades); weldability fair (42/100); formability poor (28/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with A182 F92 N+T+PWHT
Is A182 F92 easy to machine?
Machine in the N+T condition at ~200–230 HB with rigid setups, sharp coated carbide, moderate speed and heavy positive feed; the fine carbides are abrasive and work-hardening is mild but tool wear is high.
Can A182 F92 be welded?
GTAW/SMAW/SAW with matching Grade 92 consumables, 200–300 °C preheat and interpass ≤300 °C, cool to ~80–100 °C before a mandatory 755–780 °C PWHT; avoid excessive heat input to limit Type IV creep cracking in the fine-grained HAZ.
Can A182 F92 be formed, bent or molded?
Hot forge at 1100–1200 °C finishing above ~950 °C, then full re-normalize and temper; cold forming is essentially impractical.
What surface finishes work on A182 F92?
Not corrosion-resistant — protect with high-temperature paint, aluminizing, chromizing or thermal-spray coatings; no anodizing, and any coating bake must stay below the tempering temperature.
A182 F92 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 |
|---|---|---|
| C | 0.07 – 0.13 | 0.11 |
| Mn | 0.3 – 0.6 | 0.45 |
| P | ≤ 0.02 | 0.01 |
| S | ≤ 0.01 | 0 |
| Si | ≤ 0.5 | 0.25 |
| Cr | 8.5 – 9.5 | 9 |
| Wsolid-solution and Laves-phase strengthening | 1.5 – 2 | 1.75 |
| Mo | 0.3 – 0.6 | 0.45 |
| VMX carbonitride former | 0.15 – 0.25 | 0.2 |
| Nblisted as Cb in ASTM | 0.04 – 0.09 | 0.06 |
| N | 0.03 – 0.07 | 0.05 |
| Bstabilizes M23C6 | 0 – 0.01 | 0 |
| Ni | ≤ 0.4 | 0.15 |
| Alsoluble Al limit | ≤ 0.02 | 0.01 |
| Ti | ≤ 0.01 | 0 |
| Zr | ≤ 0.01 | 0 |
| Fe | balance | — |
A182 F92 N+T+PWHT — frequently asked
What is A182 F92 N+T+PWHT used for?
A182 F92 N+T+PWHT is typically used for ultra-supercritical boiler flanges, high-temperature steam valve bodies and header forgings. In short: highest-strength 9Cr forging grade; ultra-supercritical steam service; mandatory post-weld heat treatment.
What is the yield strength of A182 F92 N+T+PWHT?
A182 F92 N+T+PWHT has a typical yield strength of 480 MPa (69.6 ksi) and a tensile strength of 670 MPa (97.2 ksi) — stronger than 59% of steel grades. Strength varies by condition: see the 5 listed tempers.
Is A182 F92 N+T+PWHT easy to machine?
Not especially — machinability is rated fair (42/100, worse than 73% of steel grades). Machine in the N+T condition at ~200–230 HB with rigid setups, sharp coated carbide, moderate speed and heavy positive feed; the fine carbides are abrasive and work-hardening is mild but tool wear is high.
Can A182 F92 N+T+PWHT be welded?
With care — weldability is rated fair (42/100). GTAW/SMAW/SAW with matching Grade 92 consumables, 200–300 °C preheat and interpass ≤300 °C, cool to ~80–100 °C before a mandatory 755–780 °C PWHT; avoid excessive heat input to limit Type IV creep cracking in the fine-grained HAZ.
What surface finishes work on A182 F92 N+T+PWHT?
Not corrosion-resistant — protect with high-temperature paint, aluminizing, chromizing or thermal-spray coatings; no anodizing, and any coating bake must stay below the tempering temperature.
Can A182 F92 N+T+PWHT be formed, bent or molded?
Hot forge at 1100–1200 °C finishing above ~950 °C, then full re-normalize and temper; cold forming is essentially impractical.
What is the maximum service temperature of A182 F92 N+T+PWHT?
A182 F92 N+T+PWHT is rated for continuous use to about 620°C (1,148 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between A182 F92 N+T and A182 F92-AF?
N+T is the default condition — standard ASME/ASTM code condition for F92 flanges, valve bodies and fittings in USC steam service. AF: only an intermediate stage — untempered martensite is hard and brittle and is never acceptable for pressure service. Yield strength is 520 MPa in N+T versus 900 MPa in AF.
Sources
- ASTM A182/A182M — Forged or Rolled Alloy and Stainless Steel Pipe Flanges, Fittings, Valves and Parts for High-Temperature Service (Grade F92) — ASTM International (2024)
- ASTM A335/A335M — Seamless Ferritic Alloy-Steel Pipe for High-Temperature Service (Grade P92) — ASTM International (2022)
- ASME BPVC Section II Part D — Properties (Metric): allowable stresses, E, α, k for 9Cr-2W steels — ASME (2023)
- EN 10222-2 / EN 10216-2 X10CrWMoVNb9-2 (1.4901) — CEN (2020)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- NIMS Creep Data Sheets, ASME Grade 92 (9Cr-0.5Mo-1.8W-V-Nb) steel — NIMS (2014)
- Vallourec / Nippon Steel Grade 92 (P92/T92) product literature — Vallourec; Nippon Steel (2021)
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.