Steel ER80S-B2 PWHT-730
Heat-treated state
UNS K20900
PWHT-730 = pWHT 730 °C / 1–4 h
Used for heavy-wall P11 vessels or long soak times; over-tempering lowers strength toward the class minimum while maximising toughness and softness.
Values for the PWHT-730 condition
Other ER80S-B2 tempers and conditions
ER80S-B2 is listed in 3 conditions; see the grade overview at ER80S-B2.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
PWHT-730This page PWHT 730 °C / 1–4 h | Used for heavy-wall P11 vessels or long soak times; over-tempering lowers strength toward the class minimum while maximising toughness and softness. | 470 | 570 | 26 | 170 HB | — |
PWHT-690Default PWHT 690 °C / 1 h | Standard delivery condition for code work on P11/P12: weld metal tempered at 690 °C, giving 550 MPa-class strength with good toughness and hardness under 225 HB. | 520 | 620 | 23 | 190 HB | — |
As-welded deposit | Only for non-code or thin-section work: untempered bainite/martensite gives much higher strength and hardness but low toughness and hydrogen-crack sensitivity. | 660 | 760 | 17 | 27 HRC | — |
What is ER80S-B2 PWHT-730?
ER80S-B2 PWHT-730 is ER80S-B2 heat treated to PWHT-730 — used for heavy-wall P11 vessels or long soak times; over-tempering lowers strength toward the class minimum while maximising toughness and softness. ER80S-B2 PWHT-730 has a yield strength of 470 MPa (68.2 ksi) and a tensile strength of 570 MPa (82.7 ksi) — stronger than 57% of steel grades. Elongation at break is 26% and the elastic modulus is 205 GPa (29.7 Msi). ER80S-B2 PWHT-730 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). PWHT-690 is the default condition FabDigit quotes; PWHT-730 is available on request or by drawing note.
Advantages
- High service temperature — 550°C (1,022 °F), better than 95% of steel grades
- Ductile — tolerates forming and impact — 26%, better than 82% of steel grades
- Readily welded — 80/100, better than 79% of steel grades
ER80S-B2 PWHT-730 properties
Typical room-temperature values for ER80S-B2 PWHT-730; 10 are specific to this condition. Other listed values are ER80S-B2 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
ER80S-B2 PWHT-730 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).
Mechanical15
ER80S-B2 PWHT-730 has a yield strength of 470 MPa (68.2 ksi) and a tensile strength of 570 MPa (82.7 ksi) — stronger than 57% of steel grades. Elongation at break is 26% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
ER80S-B2 PWHT-730 is rated for continuous service to 550°C (1,022 °F). It conducts heat at 41 W/m·K (23.7 BTU/hr·ft·°F), worse than 62% of steel grades. Thermal expansion is 12.3 µm/m·K (6.83 µin/in·°F).
Electrical2
ER80S-B2 PWHT-730 has an electrical resistivity of 2.2×10⁻⁷ Ω·m.
Chemical & Environmental3
Corrosion resistance is poor (16/100), better than 79% of steel grades.
Sustainability4
Producing a kilogram of ER80S-B2 PWHT-730 takes about 32 MJ of energy and emits 2.4 kg of CO₂ — more than 70% of steel grades. Typical recycled content is 30%.
Manufacturability7
ER80S-B2 PWHT-730's machinability is good (55/100, better than 62% of steel grades); weldability very good (80/100); formability fair (45/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with ER80S-B2 PWHT-730
Is ER80S-B2 easy to machine?
PWHT weld metal machines like normalized-and-tempered 4130 (~60 % of 1212); as-welded beads are hard and best machined only after stress relief.
Can ER80S-B2 be welded?
GMAW with Ar-CO₂ (typically 75–98 % Ar) or GTAW with Ar; preheat 150–250 °C, interpass ≤ 300 °C, low-hydrogen practice, and PWHT 690–730 °C for code work on P11/P12.
Can ER80S-B2 be formed, bent or molded?
Supplied as cold-drawn, copper-coated or bright wire; keep feed-liner radii generous and store dry to avoid rust and feeding problems.
What surface finishes work on ER80S-B2?
Not corrosion resistant — weldments need aluminized coating, high-temperature paint or insulation; grind and PT/UT inspect after PWHT.
ER80S-B2 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 – 0.12 | 0.1 |
| Mn | 0.4 – 0.7 | 0.55 |
| Si | 0.4 – 0.7 | 0.55 |
| Cr | 1.2 – 1.5 | 1.35 |
| Mo | 0.4 – 0.65 | 0.5 |
| Ni | ≤ 0.2 | 0.05 |
| Cuincludes any copper coating | ≤ 0.35 | 0.15 |
| P | ≤ 0.03 | 0.01 |
| S | ≤ 0.03 | 0.01 |
| Other, totalsum of residuals per AWS A5.28 | ≤ 0.5 | — |
| Fe | balance | — |
ER80S-B2 PWHT-730 — frequently asked
What is ER80S-B2 PWHT-730 used for?
ER80S-B2 PWHT-730 is typically used for P11/P12 pipe and vessel welding, boiler tube welding, refinery reactor welds and steam piping repair. In short: standard P11/P12 filler; 80 ksi Cr-Mo deposit; service to 550 °C.
What is the yield strength of ER80S-B2 PWHT-730?
ER80S-B2 PWHT-730 has a typical yield strength of 470 MPa (68.2 ksi) and a tensile strength of 570 MPa (82.7 ksi) — stronger than 57% of steel grades. Strength varies by condition: see the 3 listed tempers.
Is ER80S-B2 PWHT-730 easy to machine?
Reasonably — machinability is rated good (55/100, better than 62% of steel grades). PWHT weld metal machines like normalized-and-tempered 4130 (~60 % of 1212); as-welded beads are hard and best machined only after stress relief.
Can ER80S-B2 PWHT-730 be welded?
Yes — weldability is rated very good (80/100). GMAW with Ar-CO₂ (typically 75–98 % Ar) or GTAW with Ar; preheat 150–250 °C, interpass ≤ 300 °C, low-hydrogen practice, and PWHT 690–730 °C for code work on P11/P12.
What surface finishes work on ER80S-B2 PWHT-730?
Not corrosion resistant — weldments need aluminized coating, high-temperature paint or insulation; grind and PT/UT inspect after PWHT.
Can ER80S-B2 PWHT-730 be formed, bent or molded?
Supplied as cold-drawn, copper-coated or bright wire; keep feed-liner radii generous and store dry to avoid rust and feeding problems.
What is the maximum service temperature of ER80S-B2 PWHT-730?
ER80S-B2 PWHT-730 is rated for continuous use to about 550°C (1,022 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between ER80S-B2 PWHT-690 and ER80S-B2-AW?
PWHT-690 is the default condition — standard delivery condition for code work on P11/P12: weld metal tempered at 690 °C, giving 550 MPa-class strength with good toughness and hardness under 225 HB. AW: only for non-code or thin-section work: untempered bainite/martensite gives much higher strength and hardness but low toughness and hydrogen-crack sensitivity. Yield strength is 520 MPa in PWHT-690 versus 660 MPa in AW.
Sources
- AWS A5.28/A5.28M — Low-Alloy Steel Electrodes and Rods for Gas Shielded Arc Welding — American Welding Society (2020)
- ASME BPVC Section II Part C, SFA-5.28 — ASME (2023)
- ASME BPVC Section II Part D — physical properties of 1¼Cr-½Mo materials — ASME (2023)
- ASM Handbook Vol. 6 — Welding, Brazing and Soldering (Cr-Mo steels) — ASM International (1993)
- Cr-Mo solid wire datasheets (Lincoln Electric, ESAB, voestalpine Böhler DCMS-Ti/IG) — various producers (2024)
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.