Steel A182 F23 N+T
Heat-treated state · default condition
ASTM A182 F23 · UNS K41650
N+T = normalized and tempered
Use the standard normalized 1040–1080 °C and tempered 730–800 °C delivery state for forgings and fittings; the tempered bainite combines room-temperature strength with 550–600 °C creep strength.
Values for the N+T condition
Other A182 F23 tempers and conditions
A182 F23 is listed in 3 conditions; see the grade overview at A182 F23.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Annealed | Use only as intermediate stock at 150 HB for rough machining or re-forming; re-normalizing and tempering before service is mandatory, since the softened state does not meet the specified properties. | 340 | 520 | 30 | 150 HB | 3.9 % IACS |
N+TDefaultThis page Normalized and tempered | Use the standard normalized 1040–1080 °C and tempered 730–800 °C delivery state for forgings and fittings; the tempered bainite combines room-temperature strength with 550–600 °C creep strength. | 480 | 600 | 25 | 185 HB | — |
Quenched and tempered | Choose for heavy-wall forgings where liquid quenching (accelerated cooling) and tempering above 730 °C secure a bainitic core, giving slightly higher strength and impact values than normalized and tempered stock. | 520 | 640 | 23 | 15 HRC | 3.8 % IACS |
What is A182 F23 N+T?
A182 F23 N+T is A182 F23 heat treated to N+T — use the standard normalized 1040–1080 °C and tempered 730–800 °C delivery state for forgings and fittings; the tempered bainite combines room-temperature strength with 550–600 °C creep strength. A182 F23 N+T has a yield strength of 480 MPa (69.6 ksi) and a tensile strength of 600 MPa (87 ksi) — stronger than 59% of steel grades. Elongation at break is 25% and the elastic modulus is 212 GPa (30.7 Msi). A182 F23 N+T has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,450°C (2,642 °F).
Advantages
- High service temperature — 600°C (1,112 °F), better than 98% of steel grades
- Tough — resists crack growth — 140 MPa·√m (127.4 ksi·√in), better than 94% of steel grades
- Ductile — tolerates forming and impact — 25%, better than 77% of steel grades
Limitations
- Poor heat conductor — 30 W/m·K (17.3 BTU/hr·ft·°F), worse than 83% of steel grades
A182 F23 N+T properties
Typical room-temperature values for A182 F23 N+T; 10 are specific to this condition. Other listed values are A182 F23 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
A182 F23 N+T has a density of 7.85 g/cm³ (0.284 lb/in³), heavier than 56% of steel grades. It melts at 1,450°C (2,642 °F).
Mechanical16
A182 F23 N+T has a yield strength of 480 MPa (69.6 ksi) and a tensile strength of 600 MPa (87 ksi) — stronger than 59% of steel grades. Elongation at break is 25% and the elastic modulus is 212 GPa (30.7 Msi).
Thermal6
A182 F23 N+T is rated for continuous service to 600°C (1,112 °F). It conducts heat at 30 W/m·K (17.3 BTU/hr·ft·°F), worse than 83% of steel grades. Thermal expansion is 11.5 µm/m·K (6.39 µin/in·°F).
Electrical2
A182 F23 N+T has an electrical resistivity of 4.5×10⁻⁷ Ω·m.
Chemical & Environmental3
Corrosion resistance is poor (18/100), better than 83% of steel grades.
Sustainability4
Producing a kilogram of A182 F23 N+T takes about 32 MJ of energy and emits 2.4 kg of CO₂ — more than 70% of steel grades. Typical recycled content is 25%.
Manufacturability6
A182 F23 N+T's machinability is fair (48/100, worse than 57% of steel grades); weldability good (65/100); formability fair (45/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with A182 F23 N+T
Is A182 F23 easy to machine?
Tempered bainitic structure at about 180–200 HB; cut with coated carbide at moderate speeds. W and V carbides raise tool wear slightly above P22, so use rigid clamping and ample coolant.
Can A182 F23 be welded?
GTAW, SMAW or SAW with 9CrWV-type T23-matching consumables (for example AWS EB9-W or ER90S-G class). Thin sections can be welded without PWHT; heavy wall should be preheated to 150–250 °C and tempered at 715–760 °C. Watch for reheat (stress-relief) cracking and for Type IV cracking after long service.
Can A182 F23 be formed, bent or molded?
Hot forge or hot bend at 1050–1150 °C, then re-normalize and temper after forming. Cold bending capability is limited and any cold deformation must be followed by restoration heat treatment.
What surface finishes work on A182 F23?
Cannot be anodized. Outer surfaces are protected with high-temperature paint, aluminizing or thermal spray; boiler internal surfaces rely on a dense oxide film and steam water chemistry control.
A182 F23 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 | 0.04 – 0.1 | 0.07 |
| Mn | 0.1 – 0.6 | 0.45 |
| Si | ≤ 0.5 | 0.25 |
| P | ≤ 0.03 | 0.01 |
| S | ≤ 0.01 | 0 |
| Cr | 1.9 – 2.6 | 2.25 |
| Mo | 0.05 – 0.3 | 0.15 |
| Wmain solid-solution strengthening element | 1.45 – 1.75 | 1.6 |
| Vforms MX-type carbonitrides | 0.2 – 0.3 | 0.25 |
| Nb | 0.02 – 0.08 | 0.05 |
| B | 5×10⁻⁴ – 0.01 | 0 |
| N | ≤ 0.03 | 0.01 |
| Al | ≤ 0.03 | 0.01 |
| Tifixes nitrogen, protects the effect of B | 0.01 – 0.06 | 0.03 |
| Fe | balance | — |
A182 F23 N+T — frequently asked
What is A182 F23 N+T used for?
A182 F23 N+T is typically used for supercritical boiler headers, steam piping flanges and membrane wall forgings. In short: higher allowable stress than P22; thin-wall welds without PWHT; 600 °C boiler forging grade.
What is the yield strength of A182 F23 N+T?
A182 F23 N+T has a typical yield strength of 480 MPa (69.6 ksi) and a tensile strength of 600 MPa (87 ksi) — stronger than 59% of steel grades. Strength varies by condition: see the 3 listed tempers.
Is A182 F23 N+T easy to machine?
Reasonably — machinability is rated fair (48/100, worse than 57% of steel grades). Tempered bainitic structure at about 180–200 HB; cut with coated carbide at moderate speeds. W and V carbides raise tool wear slightly above P22, so use rigid clamping and ample coolant.
Can A182 F23 N+T be welded?
Yes — weldability is rated good (65/100). GTAW, SMAW or SAW with 9CrWV-type T23-matching consumables (for example AWS EB9-W or ER90S-G class). Thin sections can be welded without PWHT; heavy wall should be preheated to 150–250 °C and tempered at 715–760 °C. Watch for reheat (stress-relief) cracking and for Type IV cracking after long service.
What surface finishes work on A182 F23 N+T?
Cannot be anodized. Outer surfaces are protected with high-temperature paint, aluminizing or thermal spray; boiler internal surfaces rely on a dense oxide film and steam water chemistry control.
Can A182 F23 N+T be formed, bent or molded?
Hot forge or hot bend at 1050–1150 °C, then re-normalize and temper after forming. Cold bending capability is limited and any cold deformation must be followed by restoration heat treatment.
What is the maximum service temperature of A182 F23 N+T?
A182 F23 N+T 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 A182 F23 N+T and A182 F23-ANN?
N+T is the default condition — use the standard normalized 1040–1080 °C and tempered 730–800 °C delivery state for forgings and fittings; the tempered bainite combines room-temperature strength with 550–600 °C creep strength. ANN: use only as intermediate stock at 150 HB for rough machining or re-forming; re-normalizing and tempering before service is mandatory, since the softened state does not meet the specified properties. Yield strength is 480 MPa in N+T versus 340 MPa in ANN.
Sources
- ASTM A182/A182M — Forged or Rolled Alloy and Stainless Steel Pipe Flanges, Fittings, Valves and Parts — ASTM International (2023)
- ASTM A335/A335M — Seamless Ferritic Alloy-Steel Pipe for High-Temperature Service (Grade P23) — ASTM International (2022)
- ASTM A213/A213M — Seamless Ferritic and Austenitic Alloy-Steel Boiler Tubes (Grade T23) — ASTM International (2022)
- GB/T 5310 07Cr2MoW2VNbB (2017)
- ASME BPVC Section II Part D — Material Properties (Cr-Mo-W CSEF steels) — ASME (2023)
- ASM Handbook Vol.1: Properties and Selection — Irons, Steels and High-Performance Alloys — ASM International (1990)
- Seamless boiler tube grade T23/P23 data (Vallourec / ) — producer (2022)
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.