Steel E80C-B8 PWHT
Heat-treated state · default condition
PWHT = post-weld heat treated
Standard delivered/qualified condition: tempered martensite meeting AWS A5.29 E80C-B8 mechanical requirements; use for all pressure-part service.
Values for the PWHT condition
Other E80C-B8 tempers and conditions
E80C-B8 is listed in 3 conditions; see the grade overview at E80C-B8.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
PWHTDefaultThis page Post-weld heat treated | Standard delivered/qualified condition: tempered martensite meeting AWS A5.29 E80C-B8 mechanical requirements; use for all pressure-part service. | 505 | 620 | 22 | 200 HB | — |
Normalized and tempered | Full re-normalizing and tempering of the weldment (e.g. shop-fabricated headers or repairs) to fully refine the deposit and match P9 base metal properties. | 520 | 640 | 24 | 15 HRC | 2.9 % IACS |
As-welded deposit | Condition immediately after welding — hard, low-toughness martensite; only acceptable as an intermediate state before mandatory PWHT. | 760 | 980 | 13 | 40 HRC | — |
What is E80C-B8 PWHT?
E80C-B8 PWHT is E80C-B8 heat treated to PWHT — standard delivered/qualified condition: tempered martensite meeting AWS A5.29 E80C-B8 mechanical requirements; use for all pressure-part service. E80C-B8 PWHT has a yield strength of 505 MPa (73.2 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 64% of steel grades. Elongation at break is 22% and the elastic modulus is 213 GPa (30.9 Msi). E80C-B8 PWHT has a density of 7.78 g/cm³ (0.281 lb/in³), lighter than 91% of steel grades. It melts at 1,425°C (2,597 °F).
Advantages
- High service temperature — 600°C (1,112 °F), better than 98% of steel grades
- Good corrosion resistance — 32/100, better than 96% of steel grades
Limitations
- High embodied carbon — 2.6 kg CO₂/kg, worse than 87% of steel grades
- Poor heat conductor — 28 W/m·K (16.2 BTU/hr·ft·°F), worse than 85% of steel grades
E80C-B8 PWHT properties
Typical room-temperature values for E80C-B8 PWHT; 13 are specific to this condition. Other listed values are E80C-B8 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
E80C-B8 PWHT has a density of 7.78 g/cm³ (0.281 lb/in³), lighter than 91% of steel grades. It melts at 1,425°C (2,597 °F).
Mechanical15
E80C-B8 PWHT has a yield strength of 505 MPa (73.2 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 64% of steel grades. Elongation at break is 22% and the elastic modulus is 213 GPa (30.9 Msi).
Thermal6
E80C-B8 PWHT is rated for continuous service to 600°C (1,112 °F). It conducts heat at 28 W/m·K (16.2 BTU/hr·ft·°F), worse than 85% of steel grades. Thermal expansion is 11.2 µm/m·K (6.22 µin/in·°F).
Electrical2
E80C-B8 PWHT has an electrical resistivity of 6×10⁻⁷ Ω·m.
Chemical & Environmental3
Corrosion resistance is poor (32/100), better than 96% of steel grades.
Sustainability4
Producing a kilogram of E80C-B8 PWHT takes about 32 MJ of energy and emits 2.6 kg of CO₂ — more than 70% of steel grades. Typical recycled content is 25%.
Manufacturability6
E80C-B8 PWHT's machinability is fair (42/100, worse than 73% of steel grades); weldability fair (50/100); formability poor (30/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with E80C-B8 PWHT
Is E80C-B8 easy to machine?
Machine only after PWHT (~200 HB); as-welded martensite at ~40 HRC needs carbide tooling, low speed and rigid setups.
Can E80C-B8 be welded?
Preheat 200–300 °C, interpass ≤ 350 °C, cool to 80–150 °C before a mandatory 730–760 °C / 1 h per 25 mm PWHT; use 75–80 %Ar/CO₂ or CO₂ per the classification and keep the wire dry.
Can E80C-B8 be formed, bent or molded?
Deposited metal is not intended for cold forming; any bending of welded assemblies should be done after PWHT with generous radii.
What surface finishes work on E80C-B8?
Grind or blast to remove slag/oxide; not corrosion resistant at ambient — apply high-temperature aluminium/silicone paint or leave under insulation with a suitable coating.
E80C-B8 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 |
|---|---|---|
| Cdeposited metal | 0.05 – 0.12 | 0.09 |
| Mn | ≤ 1.25 | 0.8 |
| Si | ≤ 1 | 0.4 |
| P | ≤ 0.03 | 0.02 |
| S | ≤ 0.03 | 0.01 |
| Cr | 8 – 10.5 | 9 |
| Mo | 0.85 – 1.2 | 1 |
| Ni | ≤ 0.4 | 0.15 |
| Cu | ≤ 0.35 | 0.05 |
| Fe | balance | — |
E80C-B8 PWHT — frequently asked
What is E80C-B8 PWHT used for?
E80C-B8 PWHT is typically used for 9Cr-1Mo boiler tubing, power plant superheater piping, refinery high-temperature vessels and hydrocracker units. In short: 9Cr high-temperature creep strength; PWHT-mandatory deposit; boiler and superheater filler.
What is the yield strength of E80C-B8 PWHT?
E80C-B8 PWHT has a typical yield strength of 505 MPa (73.2 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 64% of steel grades. Strength varies by condition: see the 3 listed tempers.
Is E80C-B8 PWHT easy to machine?
Not especially — machinability is rated fair (42/100, worse than 73% of steel grades). Machine only after PWHT (~200 HB); as-welded martensite at ~40 HRC needs carbide tooling, low speed and rigid setups.
Can E80C-B8 PWHT be welded?
With care — weldability is rated fair (50/100). Preheat 200–300 °C, interpass ≤ 350 °C, cool to 80–150 °C before a mandatory 730–760 °C / 1 h per 25 mm PWHT; use 75–80 %Ar/CO₂ or CO₂ per the classification and keep the wire dry.
What surface finishes work on E80C-B8 PWHT?
Grind or blast to remove slag/oxide; not corrosion resistant at ambient — apply high-temperature aluminium/silicone paint or leave under insulation with a suitable coating.
Can E80C-B8 PWHT be formed, bent or molded?
Deposited metal is not intended for cold forming; any bending of welded assemblies should be done after PWHT with generous radii.
What is the maximum service temperature of E80C-B8 PWHT?
E80C-B8 PWHT 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 E80C-B8 PWHT and E80C-B8-AW?
PWHT is the default condition — standard delivered/qualified condition: tempered martensite meeting AWS A5.29 E80C-B8 mechanical requirements; use for all pressure-part service. AW: condition immediately after welding — hard, low-toughness martensite; only acceptable as an intermediate state before mandatory PWHT. Yield strength is 505 MPa in PWHT versus 760 MPa in AW.
Sources
- AWS A5.29/A5.29M — Low-Alloy Steel Electrodes for Flux Cored Arc Welding — AWS (2010)
- ASTM A335/A335M — Seamless Ferritic Alloy-Steel Pipe (Grade P9) — ASTM (2023)
- ASME BPVC Section II Part D — Material Properties — ASME (2023)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.6 — Welding, Brazing and Soldering — ASM International (1993)
- 9Cr-1Mo cored welding wire datasheets (Böhler, ESAB, Kobelco) — various (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.