Steel ER80S-B2
UNS K20900
ER80S-B2 (K20900) is a 1.25Cr-0.5Mo solid wire in the low-alloy steel filler family and the standard consumable for welding P11/P12 chrome-moly components in elevated-temperature service.
Reference datasheet — ER80S-B2 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the PWHT-690 condition
ER80S-B2 tempers and conditions
ER80S-B2 is supplied in 3 conditions, soft to hard. PWHT-690 is the default FabDigit quotes; the values on this page are for it.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
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 | — |
Supply forms, finishes and certifications
Ways ER80S-B2 is supplied — form, process route, surface or paperwork — without a datasheet of their own. The property values above apply.
| Option | What it is | Type |
|---|---|---|
WIRE-CD | Wire, cold drawn | Supply form |
What is ER80S-B2?
ER80S-B2 (K20900) is a 1.25Cr-0.5Mo solid wire in the low-alloy steel filler family and the standard consumable for welding P11/P12 chrome-moly components in elevated-temperature service. Post-weld heat treated deposits typically show 520 MPa yield, 620 MPa tensile, 23 % elongation and 190 HB (91 HRB), with service to 550 °C; it is supplied as cold-drawn copper-coated or bright spooled wire and cut TIG rod. As-welded beads are hard, so preheat, interpass control and PWHT at 690–730 °C are required for code work, and the deposit has no corrosion resistance. Use ER70S-B2L where lower as-welded hardness is preferred. ER80S-B2 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). ER80S-B2 has a yield strength of 520 MPa (75.4 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 67% of steel grades. Elongation at break is 23% and the elastic modulus is 205 GPa (29.7 Msi).
What is ER80S-B2 used for?
- P11/P12 pipe and vessel welding
- boiler tube welding
- refinery reactor welds
- steam piping repair
Advantages
- High service temperature — 550°C (1,022 °F), better than 95% of steel grades
- Readily welded — 80/100, better than 79% of steel grades
ER80S-B2 properties
Typical room-temperature values for ER80S-B2-PWHT-690; bars are the position among steel grades.
Physical3
ER80S-B2 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 has a yield strength of 520 MPa (75.4 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 67% of steel grades. Elongation at break is 23% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
ER80S-B2 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 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 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's machinability is good (55/100, better than 62% of steel grades); weldability very good (80/100); formability fair (45/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the steel family
Yield strength against density for every steel grade FabDigit runs. ER80S-B2 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with ER80S-B2
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.
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 |
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.
Surface treatments FabDigit runs on steel parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Organic Coating
Black / Phosphate
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Steel ER80S-B2 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- K20900
- Other
- ER55S-B2
How much does ER80S-B2 cost?
ER80S-B2 is a premium-cost steel ($$$), cheaper than about 51% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
ER80S-B2 — frequently asked
What is ER80S-B2 used for?
ER80S-B2 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?
ER80S-B2 has a typical yield strength of 520 MPa (75.4 ksi) and a tensile strength of 620 MPa (89.9 ksi) — stronger than 67% of steel grades. Strength varies by condition: see the 3 listed tempers.
Is ER80S-B2 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 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?
Not corrosion resistant — weldments need aluminized coating, high-temperature paint or insulation; grind and PT/UT inspect after PWHT.
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 is the maximum service temperature of ER80S-B2?
ER80S-B2 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.
How much does ER80S-B2 cost?
ER80S-B2 is a premium-cost steel ($$$), cheaper than about 51% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
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; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.