Steel ER310
UNS S31080 · EN 25 20
ER310 is a fully austenitic 25Cr-20Ni stainless filler wire (S31080, also designated 25 20) for welding 310 and other heat-resistant stainless steels.
Reference datasheet — ER310 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
ER310 tempers and conditions
ER310 is supplied in 3 conditions, soft to hard. AW 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 |
|---|---|---|---|---|---|---|
Deposit solution annealed ~1050–1100 °C, water quenched | Use when the fabrication receives a post-weld solution anneal: dissolves carbides/σ precursors, lowers strength and raises ductility and toughness. | 300 | 550 | 42 | 160 HB | 2.2 % IACS |
AWDefault As-welded deposit | Default condition: properties of the undiluted ER310 deposit in the as-welded state (GTAW/GMAW/SAW). | 380 | 590 | 35 | 180 HB | 2.2 % IACS |
Service-aged | Reference condition for assessing repair/inspection of 25-20 weld metal after prolonged mid-temperature service; ductility and impact energy collapse. | 430 | 640 | 12 | 18 HRC | 2.1 % IACS |
Supply forms, finishes and certifications
Ways ER310 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 | Cold-drawn bare filler wire as supplied | Supply form |
What is ER310?
ER310 is a fully austenitic 25Cr-20Ni stainless filler wire (S31080, also designated 25 20) for welding 310 and other heat-resistant stainless steels. It is chosen for oxidation resistance to about 1050 °C and for high-temperature overlays and dissimilar joints, and is available as GTAW rod, GMAW spool and SAW wire; as-welded values are 380 MPa yield, 590 MPa tensile, 35 % elongation and 180 HB (89 HRB). The 0 FN deposit is hot-crack sensitive and needs low heat input, narrow beads and clean joint preparation; ER309L is the more forgiving and lower-cost option where service temperature is moderate. ER310 has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 93% of steel grades. It melts at 1,400°C (2,552 °F). ER310 has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 590 MPa (85.6 ksi) — weaker than 68% of steel grades. Elongation at break is 35% and the elastic modulus is 200 GPa (29 Msi).
What is ER310 used for?
- heat-resistant equipment
- furnace parts
- high-temperature fixtures
- dissimilar metal joints
Advantages
- High service temperature — 1,050°C (1,922 °F), better than 100% of steel grades
- Good corrosion resistance — 62/100, better than 100% of steel grades
- Tough — resists crack growth — 160 MPa·√m (145.6 ksi·√in), better than 98% of steel grades
- Ductile — tolerates forming and impact — 35%, better than 97% of steel grades
- Polishes to a fine finish — 65/100, better than 78% of steel grades
Limitations
- Poor heat conductor — 14.2 W/m·K (8.2 BTU/hr·ft·°F), worse than 99% of steel grades
- Low electrical conductivity — 2.2 % IACS, worse than 98% of steel grades
- High embodied carbon — 5.6 kg CO₂/kg, worse than 98% of steel grades
- Difficult to machine — 30/100, worse than 89% of steel grades
ER310 properties
Typical room-temperature values for ER310-AW; bars are the position among steel grades.
Physical3
ER310 has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 93% of steel grades. It melts at 1,400°C (2,552 °F).
Mechanical16
ER310 has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 590 MPa (85.6 ksi) — weaker than 68% of steel grades. Elongation at break is 35% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
ER310 is rated for continuous service to 1,050°C (1,922 °F). It conducts heat at 14.2 W/m·K (8.2 BTU/hr·ft·°F), worse than 99% of steel grades. Thermal expansion is 15.9 µm/m·K (8.83 µin/in·°F).
Electrical3
ER310 conducts electricity at 2.2 % IACS, worse than 98% of steel grades.
Chemical & Environmental3
Corrosion resistance is good (62/100), better than 100% of steel grades.
Sustainability4
Producing a kilogram of ER310 takes about 76 MJ of energy and emits 5.6 kg of CO₂ — more than 97% of steel grades. Typical recycled content is 55%.
Manufacturability8
ER310's machinability is poor (30/100, worse than 89% of steel grades); weldability good (55/100); formability good (55/100).
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. ER310 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with ER310
Is ER310 easy to machine?
Tough, gummy and rapidly work-hardening — use rigid setups, sharp positive-rake carbide, heavy positive feeds and flood coolant; avoid dwelling.
Can ER310 be welded?
GTAW/GMAW/SAW with pure Ar (add 2 % CO₂ or He for GMAW); keep interpass below ~150 °C and heat input low, weave narrow — the 0 FN fully austenitic deposit is hot-crack sensitive.
Can ER310 be formed, bent or molded?
Deposit is ductile but strongly work-hardening; cold straightening of the drawn wire is fine, heavy cold forming of the weld needs intermediate annealing.
ER310 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 C than 310S for creep strength | 0.08 – 0.15 | 0.12 |
| Cr | 25 – 28 | 26.5 |
| Ni | 20 – 22.5 | 21 |
| Mn | 1 – 2.5 | 1.8 |
| Si | 0.3 – 0.65 | 0.45 |
| Mo | ≤ 0.75 | |
| Cu | ≤ 0.75 | |
| P | ≤ 0.03 | |
| S | ≤ 0.03 | |
| Fe | balance |
What surface finishes work on ER310?
Remove weld oxide/heat tint by pickling or mechanical cleaning then passivate (ASTM A967) to restore full oxidation and corrosion resistance.
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 ER310 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- S31080
- EN / DIN / Werkstoff-Nr.
- 25 20
How much does ER310 cost?
ER310 is a high-cost 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.
ER310 — frequently asked
What is ER310 used for?
ER310 is typically used for heat-resistant equipment, furnace parts, high-temperature fixtures and dissimilar metal joints. In short: highest service temperature stainless filler; fully austenitic 25-20 deposit; hot-crack sensitive, low heat input.
What is the yield strength of ER310?
ER310 has a typical yield strength of 380 MPa (55.1 ksi) and a tensile strength of 590 MPa (85.6 ksi) — weaker than 68% of steel grades. Strength varies by condition: see the 3 listed tempers.
Is ER310 easy to machine?
Not especially — machinability is rated poor (30/100, worse than 89% of steel grades). Tough, gummy and rapidly work-hardening — use rigid setups, sharp positive-rake carbide, heavy positive feeds and flood coolant; avoid dwelling.
Can ER310 be welded?
Yes — weldability is rated good (55/100). GTAW/GMAW/SAW with pure Ar (add 2 % CO₂ or He for GMAW); keep interpass below ~150 °C and heat input low, weave narrow — the 0 FN fully austenitic deposit is hot-crack sensitive.
What surface finishes work on ER310?
Remove weld oxide/heat tint by pickling or mechanical cleaning then passivate (ASTM A967) to restore full oxidation and corrosion resistance.
Can ER310 be formed, bent or molded?
Deposit is ductile but strongly work-hardening; cold straightening of the drawn wire is fine, heavy cold forming of the weld needs intermediate annealing.
What is the maximum service temperature of ER310?
ER310 is rated for continuous use to about 1,050°C (1,922 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between ER310-AW and ER310-SA?
AW is the default condition — default condition: properties of the undiluted ER310 deposit in the as-welded state (GTAW/GMAW/SAW). SA: use when the fabrication receives a post-weld solution anneal: dissolves carbides/σ precursors, lowers strength and raises ductility and toughness. Yield strength is 380 MPa in AW versus 300 MPa in SA.
How much does ER310 cost?
ER310 is a high-cost 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 — AWS (2017)
- ASM Specialty Handbook: Stainless Steels — ASM International (1994)
- ASM Handbook Vol.6 — Welding, Brazing and Soldering — ASM International (1993)
- Stainless filler metal ER310 all-weld-metal data (typical producer datasheets) — Various filler metal producers (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.