Duplex
FERVEO DPX 2594
covered electrode · stick electrodeCatalogue only
also as: solid wireTIG rod
AWS class
E 2594 - 15
EN ISO class
E 25 9 4 N L B 42
Tensile strength (Rm)
760 MPa
Classification
| AWS class | E 2594 - 15 |
|---|---|
| EN ISO class | E 25 9 4 N L B 42 |
Purpose
- High-alloy basic duplex electrode 25Cr-9Ni-4Mo-N (AWS E2594-15) — welding super duplex steel (UNS S32750, S32760, S32550, 1.4410, 1.4501, 1.4507).
Why it works
Higher chromium, molybdenum and nitrogen content than a standard duplex (2209) raises pitting and chloride stress-corrosion resistance to levels suited to aggressive marine environments, at the cost of an even more heat-input-sensitive phase balance.
Fields of application
- Super duplex steel UNS S32750, S32760, S32550 and equivalents (1.4410, 1.4501, 1.4507); offshore and seawater applications.
- Caustic alkali and phosphoric acid environments.
Chemical composition
| Element | Typical, % |
|---|---|
| C | 0.035 |
| N | 0.25 |
| Cr | 24 |
| Mn | 1.45 |
| Mo | 3.8 |
| Ni | 8.6 |
| Si | 0.35 |
Mechanical properties
| Tensile strength (Rm) | 760 MPa |
|---|---|
| Yield strength (Rp0.2) | 550 MPa |
| Elongation (A5) | 18 % |
| Impact energy (KV) | 47 J (20 °C) |
Process
| Polarity | DC+ |
|---|---|
| Positions | PAflatPBhorizontal-verticalPChorizontalPDhorizontal-overheadPEoverheadPFvertical-up |
| Re-drying | 250°C - 300°C / min. 2h |
Sizes and part numbers
| Ø | Length | Current | Request |
|---|---|---|---|
| 2.5 mm | 250 mm | 60–80 A | |
| 3.2 mm | 300 mm | 80–120 A |
Cross-reference
| Replaces Exaton 25.10.4.LR (Exaton) | Requires WPS validation |
| Replaces BASINOX 25 10 4 N (Oerlikon) | Requires WPS validation |
Equivalence refers to the classification (AWS / EN ISO), not to product identity. In applications with a qualified procedure (WPS), validate the substitution before use.
Base metals
1.4410X2CrNiMoN 25-7-41.4501X2CrNiMoCuWN 25-7-41.4507X2CrNiMoCuN 25-6-3UNS S32750S32760S32550
Advantages
- High resistance to pitting and stress-corrosion cracking in seawater — superior to a standard duplex (2209).
- High mechanical strength in the deposit.
- Good resistance in caustic alkalis and phosphoric acid.
Limitations
- The ferrite/austenite phase balance is more heat-input-sensitive than a standard duplex — requires stricter interpass temperature control.
- Higher risk of sigma-phase embrittlement under sustained exposure in the 300–1000°C range than a standard duplex — not suited to continuous service in that range.