Stainless Steel ER330
UNS N08331
ER330 is a high-nickel fully austenitic bare wire (UNS N08331) used to weld 330-type heat-resistant alloys for very high temperature service.
Reference datasheet — ER330 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
ER330 tempers and conditions
ER330 is supplied in 5 conditions, soft to hard. AW is the default FabDigit quotes; the values on this page are for it.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Weld metal solution annealed ~1090 °C, rapid cooled | Use when the fabricated assembly is solution annealed with the base alloy to dissolve carbides and restore ductility. | 265 | 550 | 42 | 160 HB | 1.7 % IACS |
As welded, GMAW/MIG spool deposit | Pick for higher deposition rate fill passes on heavier 330-type sections; slightly lower ductility than TIG. | 375 | 560 | 29 | 195 HB | 1.7 % IACS |
AWDefault As-welded deposit | Default condition: undiluted deposit properties as used for design of 330-type heat-resistant weldments. | 380 | 570 | 31 | 190 HB | 1.7 % IACS |
As welded, GTAW/TIG deposit | Pick for thin-section, high-purity root and repair welds where the cleanest, most ductile deposit is wanted. | 390 | 590 | 33 | 190 HB | 1.7 % IACS |
Cold drawn | Property set of the filler wire itself as delivered — relevant to feedability, stiffness of TIG rods and spool handling, not to weld design. | 620 | 800 | 12 | 25 HRC | 1.7 % IACS |
What is ER330?
ER330 is a high-nickel fully austenitic bare wire (UNS N08331) used to weld 330-type heat-resistant alloys for very high temperature service. It is selected for furnace hardware and fixtures that cycle repeatedly at temperature, and is supplied as cold-drawn spool wire and cut rod for GTAW and GMAW. Deposits give about 380 MPa yield, 570 MPa tensile, 31 % elongation and 190 HB (90 HRB), with service listed to 1100 C. The fully austenitic deposit is hot-crack sensitive and the wire is expensive and thinly stocked; ER310 is the usual lower-nickel alternative. ER330 has a density of 7.94 g/cm³ (0.287 lb/in³), heavier than 78% of stainless steel grades. It melts at 1,350°C (2,462 °F). ER330 has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 570 MPa (82.7 ksi) — stronger than 52% of stainless steel grades. Elongation at break is 31% and the elastic modulus is 196 GPa (28.4 Msi).
What is ER330 used for?
- Furnace components
- Heat-treating baskets and fixtures
- Radiant tubes and retorts
- Burner nozzles and muffles
- Kiln and furnace roll repair
- Annealing box and tray fabrication
- High-temperature ducting and hangers
Advantages
- High service temperature — 1,100°C (2,012 °F), better than 96% of stainless steel grades
Limitations
- Low electrical conductivity — 1.7 % IACS, worse than 93% of stainless steel grades
- High embodied carbon — 6.5 kg CO₂/kg, worse than 93% of stainless steel grades
- Poor heat conductor — 12.5 W/m·K (7.22 BTU/hr·ft·°F), worse than 90% of stainless steel grades
- Difficult to machine — 25/100, worse than 88% of stainless steel grades
- Hard to polish — 60/100, worse than 80% of stainless steel grades
ER330 properties
Typical room-temperature values for ER330-AW; bars are the position among stainless steel grades.
Physical3
ER330 has a density of 7.94 g/cm³ (0.287 lb/in³), heavier than 78% of stainless steel grades. It melts at 1,350°C (2,462 °F).
Mechanical15
ER330 has a yield strength of 380 MPa (55.1 ksi) and a tensile strength of 570 MPa (82.7 ksi) — stronger than 52% of stainless steel grades. Elongation at break is 31% and the elastic modulus is 196 GPa (28.4 Msi).
Thermal6
ER330 is rated for continuous service to 1,100°C (2,012 °F). It conducts heat at 12.5 W/m·K (7.22 BTU/hr·ft·°F), worse than 90% of stainless steel grades. Thermal expansion is 14.6 µm/m·K (8.11 µin/in·°F).
Electrical3
ER330 conducts electricity at 1.7 % IACS, worse than 93% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (58/100), worse than 62% of stainless steel grades.
Sustainability4
Producing a kilogram of ER330 takes about 90 MJ of energy and emits 6.5 kg of CO₂ — more than 94% of stainless steel grades. Typical recycled content is 40%.
Manufacturability7
ER330's machinability is poor (25/100, worse than 88% of stainless steel grades); weldability good (60/100); 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 stainless steel family
Yield strength against density for every stainless steel grade FabDigit runs. ER330 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with ER330
Is ER330 easy to machine?
Rarely machined as wire; deposits are gummy, work-hardening and abrasive — use rigid setups, sharp carbide, heavy positive rake, low speed and flood coolant.
Can ER330 be welded?
Weld with low heat input, stringer beads, interpass temperature below ~150 °C and tight joint cleanliness; the fully austenitic deposit is hot-crack sensitive, so avoid restraint, sulphur/phosphorus pickup and excessive dilution from mild steel.
Can ER330 be formed, bent or molded?
Supplied as cold-drawn wire; the deposit itself work-hardens rapidly, so cold straightening or peening of welds should be limited and followed by a solution anneal if heavy.
ER330 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 |
|---|---|---|
| Chigh C intentional for creep/carburisation resistance | 0.18 – 0.25 | 0.21 |
| Cr | 15 – 17 | 16 |
| Ni | 34 – 37 | 35.5 |
| Mn | 1 – 2.5 | 1.7 |
| Si | 0.3 – 0.65 | 0.5 |
| Moresidual limit | ≤ 0.75 | |
| Curesidual limit | ≤ 0.75 | |
| P | ≤ 0.03 | |
| S | ≤ 0.03 | |
| Febalance, ~44 % | balance |
What surface finishes work on ER330?
Grind and pickle/passivate welds to remove heat tint and embedded iron; not anodisable, and electropolishing gives the best high-temperature oxidation performance.
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 ER330 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- N08331
How much does ER330 cost?
ER330 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.
ER330 — frequently asked
What is ER330 used for?
ER330 is typically used for furnace components, heat-treating baskets and fixtures, radiant tubes and retorts, burner nozzles and muffles, kiln and furnace roll repair and annealing box and tray fabrication. In short: highest service temperature filler; furnace-grade high-Ni wire; fully austenitic deposit.
What is the yield strength of ER330?
ER330 has a typical yield strength of 380 MPa (55.1 ksi) and a tensile strength of 570 MPa (82.7 ksi) — stronger than 52% of stainless steel grades. Strength varies by condition: see the 5 listed tempers.
Is ER330 easy to machine?
Not especially — machinability is rated poor (25/100, worse than 88% of stainless steel grades). Rarely machined as wire; deposits are gummy, work-hardening and abrasive — use rigid setups, sharp carbide, heavy positive rake, low speed and flood coolant.
Can ER330 be welded?
Yes — weldability is rated good (60/100). Weld with low heat input, stringer beads, interpass temperature below ~150 °C and tight joint cleanliness; the fully austenitic deposit is hot-crack sensitive, so avoid restraint, sulphur/phosphorus pickup and excessive dilution from mild steel.
What surface finishes work on ER330?
Grind and pickle/passivate welds to remove heat tint and embedded iron; not anodisable, and electropolishing gives the best high-temperature oxidation performance.
Can ER330 be formed, bent or molded?
Supplied as cold-drawn wire; the deposit itself work-hardens rapidly, so cold straightening or peening of welds should be limited and followed by a solution anneal if heavy.
What is the maximum service temperature of ER330?
ER330 is rated for continuous use to about 1,100°C (2,012 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between ER330-AW and ER330-CD?
AW is the default condition — default condition: undiluted deposit properties as used for design of 330-type heat-resistant weldments. CD: property set of the filler wire itself as delivered — relevant to feedability, stiffness of TIG rods and spool handling, not to weld design. Yield strength is 380 MPa in AW versus 620 MPa in CD.
How much does ER330 cost?
ER330 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 (ER330, UNS W88331) — AWS (2017)
- ASME BPVC Section II Part C, SFA-5.9 — ASME (2023)
- ASM Handbook Vol.6 Welding, Brazing and Soldering; Vol.1 Properties of Irons and Steels — ASM International (1993)
- Alloy 330 / RA330 heat-resistant alloy physical property datasheet — Rolled Alloys (2022)
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.