Steel ER90S-B3 PWHT730
Heat-treated state
UNS K30960
Higher-temperature field PWHT used on thick P22 welds; softer and tougher deposit, strength approaches the lower end of the 620 MPa class.
Values for the PWHT730 condition
Other ER90S-B3 tempers and conditions
ER90S-B3 is listed in 3 conditions; see the grade overview at ER90S-B3.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
PWHT730This page PWHT | Higher-temperature field PWHT used on thick P22 welds; softer and tougher deposit, strength approaches the lower end of the 620 MPa class. | 530 | 640 | 24 | 185 HB | 8 % IACS |
PWHT690Default PWHT | Standard condition for P22 piping and vessels: meets the 620 MPa / 530 MPa AWS minima with good toughness. | 580 | 680 | 21 | 205 HB | — |
As-welded deposit | Untempered bainitic/martensitic deposit — high strength and hardness but low toughness and hydrogen-cracking risk; acceptable only where code permits no PWHT. | 700 | 820 | 17 | 30 HRC | — |
What is ER90S-B3 PWHT730?
ER90S-B3 PWHT730 is ER90S-B3 heat treated to PWHT730 — higher-temperature field PWHT used on thick P22 welds; softer and tougher deposit, strength approaches the lower end of the 620 MPa class. ER90S-B3 PWHT730 has a yield strength of 530 MPa (76.9 ksi) and a tensile strength of 640 MPa (92.8 ksi) — stronger than 69% of steel grades. Elongation at break is 24% and the elastic modulus is 207 GPa (30 Msi). ER90S-B3 PWHT730 has a density of 7.83 g/cm³ (0.283 lb/in³), lighter than 80% of steel grades. It melts at 1,450°C (2,642 °F). PWHT690 is the default condition FabDigit quotes; PWHT730 is available on request or by drawing note.
Advantages
- Tough — resists crack growth — 155 MPa·√m (141.1 ksi·√in), better than 97% of steel grades
- High service temperature — 580°C (1,076 °F), better than 97% of steel grades
Limitations
- High embodied carbon — 2.6 kg CO₂/kg, worse than 87% of steel grades
ER90S-B3 PWHT730 properties
Typical room-temperature values for ER90S-B3 PWHT730; 22 are specific to this condition. Other listed values are ER90S-B3 reference data and may not represent this condition. Bars are the position among steel grades.
Physical3
ER90S-B3 PWHT730 has a density of 7.83 g/cm³ (0.283 lb/in³), lighter than 80% of steel grades. It melts at 1,450°C (2,642 °F).
Mechanical15
ER90S-B3 PWHT730 has a yield strength of 530 MPa (76.9 ksi) and a tensile strength of 640 MPa (92.8 ksi) — stronger than 69% of steel grades. Elongation at break is 24% and the elastic modulus is 207 GPa (30 Msi).
Thermal6
ER90S-B3 PWHT730 is rated for continuous service to 580°C (1,076 °F). It conducts heat at 38 W/m·K (22 BTU/hr·ft·°F), worse than 69% of steel grades. Thermal expansion is 12.3 µm/m·K (6.83 µin/in·°F).
Electrical3
ER90S-B3 PWHT730 conducts electricity at 8 % IACS, better than 55% of steel grades.
Chemical & Environmental2
Corrosion resistance is poor (20/100), better than 87% of steel grades.
Sustainability4
Producing a kilogram of ER90S-B3 PWHT730 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
ER90S-B3 PWHT730's machinability is fair (50/100, worse than 53% of steel grades); weldability very good (70/100); formability fair (50/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with ER90S-B3 PWHT730
Is ER90S-B3 easy to machine?
Machine the deposit after PWHT; as-welded bainite at ~30 HRC dulls carbide tooling quickly.
Can ER90S-B3 be welded?
GTAW/GMAW/SAW with Ar or Ar-CO₂; preheat 200–260 °C, interpass ≤ 315 °C, low-hydrogen practice, and PWHT 690–760 °C to temper the deposit and avoid hydrogen cracking.
Can ER90S-B3 be formed, bent or molded?
Supplied as drawn wire (spools, 1000 mm cut lengths); no user forming — protect from moisture and handle with clean gloves.
What surface finishes work on ER90S-B3?
Weld deposits are usually ground/blended and then painted or insulated; no anodizing, and the alloy rusts if left bare.
ER90S-B3 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 |
|---|---|---|
| Chigher than the 'L' (low-carbon) variant | 0.07 – 0.12 | 0.1 |
| Mn | 0.4 – 0.7 | 0.55 |
| Si | 0.4 – 0.7 | 0.55 |
| Cr | 2.3 – 2.7 | 2.5 |
| Mo | 0.9 – 1.2 | 1.05 |
| Ni | ≤ 0.2 | 0.05 |
| Cuincludes any copper coating | ≤ 0.35 | 0.1 |
| P | ≤ 0.03 | 0.01 |
| S | ≤ 0.03 | 0.01 |
| other (total)total of other elements | ≤ 0.5 | — |
| Fe | balance | — |
ER90S-B3 PWHT730 — frequently asked
What is ER90S-B3 PWHT730 used for?
ER90S-B3 PWHT730 is typically used for P22 high-strength piping welds, power plant boiler components and hydroprocessing reactor welds. In short: matched P22 filler wire; stronger than B3L; 580 °C service rating.
What is the yield strength of ER90S-B3 PWHT730?
ER90S-B3 PWHT730 has a typical yield strength of 530 MPa (76.9 ksi) and a tensile strength of 640 MPa (92.8 ksi) — stronger than 69% of steel grades. Strength varies by condition: see the 3 listed tempers.
Is ER90S-B3 PWHT730 easy to machine?
Reasonably — machinability is rated fair (50/100, worse than 53% of steel grades). Machine the deposit after PWHT; as-welded bainite at ~30 HRC dulls carbide tooling quickly.
Can ER90S-B3 PWHT730 be welded?
Yes — weldability is rated very good (70/100). GTAW/GMAW/SAW with Ar or Ar-CO₂; preheat 200–260 °C, interpass ≤ 315 °C, low-hydrogen practice, and PWHT 690–760 °C to temper the deposit and avoid hydrogen cracking.
What surface finishes work on ER90S-B3 PWHT730?
Weld deposits are usually ground/blended and then painted or insulated; no anodizing, and the alloy rusts if left bare.
Can ER90S-B3 PWHT730 be formed, bent or molded?
Supplied as drawn wire (spools, 1000 mm cut lengths); no user forming — protect from moisture and handle with clean gloves.
What is the maximum service temperature of ER90S-B3 PWHT730?
ER90S-B3 PWHT730 is rated for continuous use to about 580°C (1,076 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between ER90S-B3 PWHT690 and ER90S-B3-AW?
PWHT690 is the default condition — standard condition for P22 piping and vessels: meets the 620 MPa / 530 MPa AWS minima with good toughness. AW: untempered bainitic/martensitic deposit — high strength and hardness but low toughness and hydrogen-cracking risk; acceptable only where code permits no PWHT. Yield strength is 580 MPa in PWHT690 versus 700 MPa in AW.
Sources
- AWS A5.28/A5.28M — Low-Alloy Steel Electrodes and Rods for Gas Shielded Arc Welding — AWS (2020)
- ASME BPVC Section II Part C (SFA-5.28) and Part D (2.25Cr-1Mo physical properties) — ASME (2023)
- ASM Handbook Vol.1 & Vol.6 — Cr-Mo steels and weld metals — ASM International (2005)
- 2.25Cr-1Mo TIG/MIG wire datasheets (Böhler DCMS-IG, Lincoln LNT/Techalloy, ESAB OK Tigrod 13.20) — 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.