Stainless Steel ER2594
ER2594 (S39594) is the bare wire counterpart to the E2594 covered electrode, a 25Cr super duplex filler for GTAW, GMAW and SAW welding of 2507 super duplex stainless.
Reference datasheet — ER2594 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 AW condition
ER2594 tempers and conditions
ER2594 is supplied in 4 conditions, soft to hard. AW is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed ~1080–1120 °C + water quench | Specify solution annealing at 1080–1120 °C with water quench when phase balance and corrosion resistance must be fully restored, as on overlays and repair-welded castings. | 600 | 820 | 32 | 24 HRC | 2.2 % IACS |
As-welded submerged-arc deposit with basic flux | Pick for high heat-input submerged-arc welding of heavy-wall pipe and pressure vessels; run with basic flux and limit interpass temperature, accepting 640 MPa yield. | 640 | 850 | 25 | 25 HRC | 2.2 % IACS |
As-welded MIG/pulsed-MIG deposit | Use for high-productivity multi-layer welding of thick sections; the higher heat input of MIG/pulsed-MIG makes ferrite control and toughness requirements stricter. | 660 | 870 | 25 | 27 HRC | 2.2 % IACS |
AWDefault As-welded deposit | Default pick for butt joints and overlays on 2507/S32760 super duplex, deposited by GTAW under Ar+2%N₂ typical shielding and used as welded with no post-weld heat treatment. | 680 | 880 | 27 | 26 HRC | 2.2 % IACS |
Supply forms, finishes and certifications
Ways ER2594 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 | Bare drawn wire / cut length as supplied | Supply form |
What is ER2594?
ER2594 (S39594) is the bare wire counterpart to the E2594 covered electrode, a 25Cr super duplex filler for GTAW, GMAW and SAW welding of 2507 super duplex stainless. It is used where both high strength and high pitting resistance are required, with deposits typically at 680 MPa yield, 880 MPa tensile, 27% elongation and 26 HRC and the highest corrosion rating in this filler group (88). It needs controlled heat input, nitrogen-bearing shielding and backing gas, and is limited to about 250 °C in service. ER2209 is the standard-duplex alternative. ER2594 has a density of 7.8 g/cm³ (0.282 lb/in³), heavier than 50% of stainless steel grades. It melts at 1,350°C (2,462 °F). ER2594 has a yield strength of 680 MPa (98.6 ksi) and a tensile strength of 880 MPa (128 ksi) — stronger than 91% of stainless steel grades. Elongation at break is 27% and the elastic modulus is 200 GPa (29 Msi).
What is ER2594 used for?
- Super duplex subsea equipment
- High-strength corrosion-resistant piping
- Subsea manifolds and connectors
- Offshore riser and firewater systems
- Chemical process vessels in chloride service
- Heat exchanger welds in seawater service
- Pitting-resistant weld overlay
Advantages
- Good corrosion resistance — 88/100, better than 97% of stainless steel grades
- High strength — 680 MPa (98.6 ksi), better than 91% of stainless steel grades
- Readily welded — 80/100, better than 80% of stainless steel grades
Limitations
- Limited service temperature — 250°C (482 °F), worse than 99% of stainless steel grades
- Difficult to machine — 25/100, worse than 88% of stainless steel grades
- High embodied carbon — 5.5 kg CO₂/kg, worse than 77% of stainless steel grades
ER2594 properties
Typical room-temperature values for ER2594-AW; bars are the position among stainless steel grades.
Physical3
ER2594 has a density of 7.8 g/cm³ (0.282 lb/in³), heavier than 50% of stainless steel grades. It melts at 1,350°C (2,462 °F).
Mechanical17
ER2594 has a yield strength of 680 MPa (98.6 ksi) and a tensile strength of 880 MPa (128 ksi) — stronger than 91% of stainless steel grades. Elongation at break is 27% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
ER2594 is rated for continuous service to 250°C (482 °F). It conducts heat at 16 W/m·K (9.24 BTU/hr·ft·°F), better than 58% of stainless steel grades. Thermal expansion is 13 µm/m·K (7.22 µin/in·°F).
Electrical3
ER2594 conducts electricity at 2.2 % IACS, worse than 61% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is excellent (88/100), better than 97% of stainless steel grades.
Sustainability4
Producing a kilogram of ER2594 takes about 55 MJ of energy and emits 5.5 kg of CO₂ — more than 50% of stainless steel grades. Typical recycled content is 55%.
Manufacturability7
ER2594's machinability is poor (25/100, worse than 88% of stainless steel grades); weldability very good (80/100); formability fair (35/100).
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 stainless steel family
Yield strength against density for every stainless steel grade FabDigit runs. ER2594 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with ER2594
Is ER2594 easy to machine?
Weld metal work-hardens strongly and has low thermal conductivity; use rigid clamping, sharp carbide tooling, low speed with heavy feed and generous coolant.
Can ER2594 be welded?
Suitable for GTAW, GMAW and SAW. Control heat input to about 0.5–1.5 kJ/mm and interpass temperature to ≤150 °C, and use Ar + 1–3% N₂ for shielding and backing to maintain nitrogen content and phase balance.
Can ER2594 be formed, bent or molded?
As a filler metal it is not normally formed. Deposits have limited cold formability, so bend to large radii and keep high-strain areas away from the weld.
ER2594 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 | ≤ 0.03 | 0.02 |
| Cr | 24 – 27 | 25.5 |
| NiHigher than 2507 base metal; ensures as-welded austenite ratio | 8 – 10.5 | 9.5 |
| Mo | 2.5 – 4.5 | 4 |
| N | 0.2 – 0.3 | 0.25 |
| Mn | ≤ 2.5 | 0.5 |
| Si | ≤ 1 | 0.4 |
| Cu | ≤ 1.5 | 0.3 |
| W | ≤ 1 | 0.2 |
| P | ≤ 0.03 | 0.02 |
| S | ≤ 0.03 | 0.01 |
| Fe | balance |
What surface finishes work on ER2594?
Heat tint must be removed after welding by pickling and passivation, or by mechanical grinding plus passivation, to restore the passive film. Electropolishing is possible; anodizing is not.
Surface treatments FabDigit runs on stainless 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).
Passivation
Organic Coating
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Stainless Steel ER2594 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- Similar grades
- S39594
How much does ER2594 cost?
ER2594 is a high-cost stainless steel ($$$$), pricier than about 78% 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.
ER2594 — frequently asked
What is ER2594 used for?
ER2594 is typically used for super duplex subsea equipment, high-strength corrosion-resistant piping, subsea manifolds and connectors, offshore riser and firewater systems, chemical process vessels in chloride service and heat exchanger welds in seawater service. In short: highest-alloy duplex filler; 2507 super duplex match; best pitting resistance here.
What is the yield strength of ER2594?
ER2594 has a typical yield strength of 680 MPa (98.6 ksi) and a tensile strength of 880 MPa (128 ksi) — stronger than 91% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.
Is ER2594 easy to machine?
Not especially — machinability is rated poor (25/100, worse than 88% of stainless steel grades). Weld metal work-hardens strongly and has low thermal conductivity; use rigid clamping, sharp carbide tooling, low speed with heavy feed and generous coolant.
Can ER2594 be welded?
Yes — weldability is rated very good (80/100). Suitable for GTAW, GMAW and SAW. Control heat input to about 0.5–1.5 kJ/mm and interpass temperature to ≤150 °C, and use Ar + 1–3% N₂ for shielding and backing to maintain nitrogen content and phase balance.
What surface finishes work on ER2594?
Heat tint must be removed after welding by pickling and passivation, or by mechanical grinding plus passivation, to restore the passive film. Electropolishing is possible; anodizing is not.
Can ER2594 be formed, bent or molded?
As a filler metal it is not normally formed. Deposits have limited cold formability, so bend to large radii and keep high-strain areas away from the weld.
What is the maximum service temperature of ER2594?
ER2594 is rated for continuous use to about 250°C (482 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between ER2594-AW and ER2594-SA?
AW is the default condition — default pick for butt joints and overlays on 2507/S32760 super duplex, deposited by GTAW under Ar+2%N₂ typical shielding and used as welded with no post-weld heat treatment. SA: specify solution annealing at 1080–1120 °C with water quench when phase balance and corrosion resistance must be fully restored, as on overlays and repair-welded castings. Yield strength is 680 MPa in AW versus 600 MPa in SA.
How much does ER2594 cost?
ER2594 is a high-cost stainless steel ($$$$), pricier than about 78% 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 A5.9/A5.9M — Bare Stainless Steel Welding Electrodes and Rods (ER2594, UNS S39594) — AWS (2017)
- ASTM A276/A790 & ASTM A923 (duplex acceptance) — ASTM (2020)
- Super duplex filler metal 2594 data sheets — ESAB / Böhler Welding / Sandvik (2023)
- ASM Handbook Vol.6A — Welding of Duplex Stainless Steels — ASM International (2011)
- SAF 2507 / Forta SDX 2507 base-metal physical property data — Alleima (Sandvik) / Outokumpu (2023)
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.