Steel ER309L
UNS S30983 · ASTM A5.9 · EN 23 12 L · JIS YS309L, Y309L · GB H08Cr23Ni13, H309L
ER309L is a low-carbon 23Cr-13Ni austenitic filler (AWS A5.9, UNS S30983, also listed as 23 12 L, H08Cr23Ni13, YS309L) for dissimilar-metal joints and overlay work.
Reference datasheet — ER309L 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
ER309L tempers and conditions
ER309L is supplied in 6 conditions, soft to hard. AW is the default FabDigit quotes; the values on this page are for it.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution Annealed deposit | Used on clad components requiring maximum corrosion resistance and dissolution of carbides/sigma; lowers strength, raises ductility. | 300 | 540 | 45 | 160 HB | 2.4 % IACS |
As Welded | Pick for heavy-section overlay and pressure-vessel cladding; flux choice controls Cr/Si recovery and ferrite. | 380 | 560 | 35 | 175 HB | 2.3 % IACS |
As Welded | Pick for root passes, thin sections and clean low-oxygen deposits with the highest toughness. | 390 | 570 | 40 | 180 HB | 2.3 % IACS |
Post-Weld Stress Relieved | Applies when the ferritic base metal demands PWHT; ductility and toughness drop from carbide/sigma precipitation in the deposit. | 395 | 570 | 32 | 195 HB | 2.4 % IACS |
AWDefault As-welded deposit | Default condition: properties of the undiluted deposit as laid down, no post-weld heat treatment. | 400 | 580 | 38 | 11 HRC | 2.3 % IACS |
As Welded | Pick for higher deposition rate fill passes and overlay cladding on carbon steel. | 410 | 590 | 36 | 190 HB | 2.3 % IACS |
Supply forms, finishes and certifications
Ways ER309L 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-CD | Cold Drawn Wire | Supply form |
What is ER309L?
ER309L is a low-carbon 23Cr-13Ni austenitic filler (AWS A5.9, UNS S30983, also listed as 23 12 L, H08Cr23Ni13, YS309L) for dissimilar-metal joints and overlay work. Typical deposits give about 400 MPa yield, 580 MPa tensile, 38 % elongation and 185 HB (90 HRB), with scaling resistance quoted to 1000 °C; forms include GTAW rod, GMAW spool and SAW wire or strip. The extra Cr and Ni absorb dilution when joining carbon or low-alloy steel to 304-type stainless. Cost is well above carbon steel fillers, and for stainless-to-stainless joints ER308L or ER316L is the correct choice. ER309L 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). ER309L has a yield strength of 400 MPa (58 ksi) and a tensile strength of 580 MPa (84.1 ksi) — weaker than 60% of steel grades. Elongation at break is 38% and the elastic modulus is 196 GPa (28.4 Msi).
What is ER309L used for?
- dissimilar metal joints
- stainless-to-carbon steel welding
- overlay/cladding
Advantages
- High service temperature — 1,000°C (1,832 °F), better than 100% of steel grades
- Good corrosion resistance — 68/100, better than 100% of steel grades
- Ductile — tolerates forming and impact — 38%, better than 98% of steel grades
- Tough — resists crack growth — 150 MPa·√m (136.5 ksi·√in), better than 96% of steel grades
- Readily welded — 90/100, better than 90% of steel grades
Limitations
- Poor heat conductor — 15.5 W/m·K (8.96 BTU/hr·ft·°F), worse than 98% of steel grades
- Low electrical conductivity — 2.3 % IACS, worse than 98% of steel grades
- High embodied carbon — 4.6 kg CO₂/kg, worse than 96% of steel grades
- Difficult to machine — 35/100, worse than 84% of steel grades
ER309L properties
Typical room-temperature values for ER309L-AW; bars are the position among steel grades.
Physical3
ER309L 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).
Mechanical17
ER309L has a yield strength of 400 MPa (58 ksi) and a tensile strength of 580 MPa (84.1 ksi) — weaker than 60% of steel grades. Elongation at break is 38% and the elastic modulus is 196 GPa (28.4 Msi).
Thermal6
ER309L is rated for continuous service to 1,000°C (1,832 °F). It conducts heat at 15.5 W/m·K (8.96 BTU/hr·ft·°F), worse than 98% of steel grades. Thermal expansion is 15.5 µm/m·K (8.61 µin/in·°F).
Electrical3
ER309L conducts electricity at 2.3 % IACS, worse than 98% of steel grades.
Chemical & Environmental3
Corrosion resistance is good (68/100), better than 100% of steel grades.
Sustainability4
Producing a kilogram of ER309L takes about 55 MJ of energy and emits 4.6 kg of CO₂ — more than 94% of steel grades. Typical recycled content is 60%.
Manufacturability7
ER309L's machinability is fair (35/100, worse than 84% of steel grades); weldability excellent (90/100); formability good (60/100).
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. ER309L is highlighted; hover a dot for its name, or open the interactive family chart.
Working with ER309L
Is ER309L easy to machine?
Deposit machines like 309/304 — tough, gummy and work-hardening; use sharp positive-rake carbide, heavy feed, no dwelling, and flood coolant.
Can ER309L be welded?
Run stringer beads with low heat input and interpass ≤150 °C; keep 8–15 FN ferrite to avoid hot cracking, and use it as a buttering layer before joining CS to stainless.
Can ER309L be formed, bent or molded?
Supplied as drawn wire only; deposits are ductile (≥30 % elongation) but strongly work-hardening, so cold straightening of clad parts should be limited.
ER309L 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 |
|---|---|---|
| CL = low carbon, limits sensitisation | ≤ 0.03 | 0.02 |
| Cr | 23 – 25 | 24 |
| Ni | 12 – 14 | 13 |
| Mn | 1 – 2.5 | 1.8 |
| Sisome producers supply Si-controlled variants | 0.3 – 0.65 | 0.45 |
| Moresidual | ≤ 0.75 | 0.1 |
| Curesidual | ≤ 0.75 | 0.15 |
| P | ≤ 0.03 | 0.02 |
| S | ≤ 0.03 | 0.01 |
| Fe | balance |
What surface finishes work on ER309L?
Pickle and passivate or electropolish after welding to remove heat tint; deposit takes a good but slightly duller polish than 304 due to delta ferrite.
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 ER309L in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- S30983
- ASTM
- A5.9
- EN / DIN / Werkstoff-Nr.
- 23 12 L
- GB (China)
- H08Cr23Ni13H309L
- JIS
- YS309LY309L
How much does ER309L cost?
ER309L 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.
ER309L — frequently asked
What is ER309L used for?
ER309L is typically used for dissimilar metal joints, stainless-to-carbon steel welding and overlay/cladding. In short: standard dissimilar-metal filler; tolerates carbon steel dilution; buttering and cladding wire.
What is the yield strength of ER309L?
ER309L has a typical yield strength of 400 MPa (58 ksi) and a tensile strength of 580 MPa (84.1 ksi) — weaker than 60% of steel grades. Strength varies by condition: see the 6 listed tempers.
Is ER309L easy to machine?
Not especially — machinability is rated fair (35/100, worse than 84% of steel grades). Deposit machines like 309/304 — tough, gummy and work-hardening; use sharp positive-rake carbide, heavy feed, no dwelling, and flood coolant.
Can ER309L be welded?
Yes — weldability is rated excellent (90/100). Run stringer beads with low heat input and interpass ≤150 °C; keep 8–15 FN ferrite to avoid hot cracking, and use it as a buttering layer before joining CS to stainless.
What surface finishes work on ER309L?
Pickle and passivate or electropolish after welding to remove heat tint; deposit takes a good but slightly duller polish than 304 due to delta ferrite.
Can ER309L be formed, bent or molded?
Supplied as drawn wire only; deposits are ductile (≥30 % elongation) but strongly work-hardening, so cold straightening of clad parts should be limited.
What is the maximum service temperature of ER309L?
ER309L is rated for continuous use to about 1,000°C (1,832 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between ER309L-AW and ER309L SA-1040?
AW is the default condition — default condition: properties of the undiluted deposit as laid down, no post-weld heat treatment. SA-1040: used on clad components requiring maximum corrosion resistance and dissolution of carbides/sigma; lowers strength, raises ductility. Yield strength is 400 MPa in AW versus 300 MPa in SA-1040.
How much does ER309L cost?
ER309L 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)
- GB/T 29713 (H08Cr23Ni13 / ER309L) — SAC (2017)
- ISO 14343 / EN 14343 — 23 12 L — ISO (2017)
- ASM Handbook Vol.6 — Welding, Brazing and Soldering — ASM International (1993)
- ASM Handbook Vol.1 — Properties of Stainless Steels (Type 309/309S) — ASM International (1990)
- ER309L solid wire all-weld-metal data (Böhler/ESAB/Lincoln/ ) — various welding consumable 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.