ER310 – wire and rod for 310 stainless and high-temperature service
Fully austenitic 25Cr-20Ni filler metal for 310 stainless and parts working under oxidation at elevated temperatures, such as furnaces and burners.
Product forms and equivalents
| Process | Classification |
|---|---|
| TIG rod (GTAW) | ER310 |
| Solid MIG/MAG wire (GMAW) | ER310 |
| Covered electrode (SMAW) | E310-16/-15 – AWS A5.4 |
| Flux-cored wire (FCAW) | E310T0-1/-4 – AWS A5.22 |
| Submerged arc wire (SAW) | ER310 + flux |
| Designation | Value |
|---|---|
| AWS | ER310 |
| Specification | AWS A5.9/A5.9M / ASME SFA-5.9 |
| UNS | S31080 |
| Others | EN ISO 14343-A: W/G 25 20; W.Nr. 1.4842 |
Chemical composition (%)
| Element | wt. % |
|---|---|
| C | 0.08 – 0.15 |
| Cr | 25.0 – 28.0 |
| Ni | 20.0 – 22.5 |
| Mo | ≤ 0.75 |
| Mn | 1.0 – 2.5 |
| Si | 0.30 – 0.65 |
| P | ≤ 0.03 |
| S | ≤ 0.03 |
| Cu | ≤ 0.75 |
Properties of the deposited metal
| Property | Value |
|---|---|
| Tensile strength of deposited metal | ≥ 550 MPa (AWS A5.4 minimum for E310, reference) |
| Elongation | ≥ 30 % (AWS A5.4 minimum for E310, reference) |
Materials welded with ER310
Dissimilar joints: Used in repairs of 446 ferritic stainless and in joints between heat-resisting stainless steels. For joining stainless to carbon steel, ER309L is indicated, or ERNiCr-3 in service above about 370 °C: the 100 % austenitic bead of ER310, diluted with carbon steel, tends to hot crack.
Why the composition differs from the base metal
Carbon is kept between 0.08 and 0.15 % to guarantee hot strength, and the bead comes out without ferrite. This avoids the sigma-phase embrittlement that ferrite would suffer in long exposures at 600–900 °C, but requires care against hot cracking.
Welding precautions
- Fully austenitic deposit: use low heat input, stringer beads and well-filled craters to avoid hot cracking.
- Interpass below 150 °C.
- TIG shielding with pure argon; in MIG/MAG use argon with 1–2 % O2 or 2–3 % CO2. Argon root purge in tubes.
Frequently asked questions
What is ER310 used for?
Fully austenitic 25Cr-20Ni filler metal for 310 stainless and parts working under oxidation at elevated temperatures, such as furnaces and burners.
Why is the composition of ER310 different from the material it welds?
Carbon is kept between 0.08 and 0.15 % to guarantee hot strength, and the bead comes out without ferrite. This avoids the sigma-phase embrittlement that ferrite would suffer in long exposures at 600–900 °C, but requires care against hot cracking.
Which covered electrode corresponds to ER310?
E310-16/-15 – AWS A5.4.
What precautions apply when welding with ER310?
Fully austenitic deposit: use low heat input, stringer beads and well-filled craters to avoid hot cracking. Interpass below 150 °C. TIG shielding with pure argon; in MIG/MAG use argon with 1–2 % O2 or 2–3 % CO2. Argon root purge in tubes.
