Stainless Steel E309H
ASTM A5.4
E309H is a higher-carbon version of the 309-type austenitic stainless electrode to AWS A5.4 (UNS W30910), with carbon deliberately held up to improve elevated-temperature creep strength.
Reference datasheet — E309H 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
E309H tempers and conditions
E309H 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 |
|---|---|---|---|---|---|---|
Post-weld heat treated | Applies when the Cr-Mo or carbon-steel side requires code PWHT; expect carbide precipitation and partial ferrite transformation with a toughness drop. | 390 | 580 | 30 | 200 HB | 2.3 % IACS |
Long-term service exposure 600–900 °C | Reference condition for fitness-for-service assessment of aged 309H weldments — strength holds up but room-temperature ductility and toughness collapse. | 410 | 620 | 15 | 20 HRC | 2.4 % IACS |
AWDefault As-welded deposit | Default condition for E309H covered electrodes: dissimilar joints, clad restoration and 304H/309H/310H high-temperature service without PWHT. | 420 | 600 | 35 | 190 HB | 2.2 % IACS |
As welded, flux-cored wire deposit | Choose for high deposition rate overlay and position welding of dissimilar/clad joints; toughness is lower than GTAW. | 420 | 590 | 32 | 195 HB | 2.2 % IACS |
AW-GTAW/GMAW | Pick when a clean, low-oxygen deposit with the best toughness and root-pass quality is needed (tube welds, orbital, clad overlay root). | 440 | 620 | 38 | 185 HB | 2.2 % IACS |
What is E309H?
E309H is a higher-carbon version of the 309-type austenitic stainless electrode to AWS A5.4 (UNS W30910), with carbon deliberately held up to improve elevated-temperature creep strength. It is used for dissimilar-metal joints and clad overlays on high-temperature equipment, and is available for SMAW, GTAW and FCAW deposition. Typical as-welded properties are about 420 MPa yield, 600 MPa tensile, 35 % elongation and 190 HB, with service to roughly 980 °C. Corrosion performance is lower than the low-carbon types, so use E309L or E309LMo where sensitisation or wet corrosion governs. E309H has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 68% of stainless steel grades. It melts at 1,400°C (2,552 °F). E309H has a yield strength of 420 MPa (60.9 ksi) and a tensile strength of 600 MPa (87 ksi) — stronger than 64% of stainless steel grades. Elongation at break is 35% and the elastic modulus is 195 GPa (28.3 Msi).
What is E309H used for?
- High-temperature dissimilar-metal joints
- Clad overlay on furnace and boiler components
- Stainless-to-carbon-steel transition welds in hot service
- Heat-treatment fixture and retort repair
- Buffer layers under high-temperature surfacing
- Petrochemical reformer and heater component welds
Advantages
- Readily welded — 88/100, better than 91% of stainless steel grades
- High service temperature — 980°C (1,796 °F), better than 87% of stainless steel grades
Limitations
- Hard to polish — 55/100, worse than 89% of stainless steel grades
E309H properties
Typical room-temperature values for E309H-AW; bars are the position among stainless steel grades.
Physical3
E309H has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 68% of stainless steel grades. It melts at 1,400°C (2,552 °F).
Mechanical16
E309H has a yield strength of 420 MPa (60.9 ksi) and a tensile strength of 600 MPa (87 ksi) — stronger than 64% of stainless steel grades. Elongation at break is 35% and the elastic modulus is 195 GPa (28.3 Msi).
Thermal6
E309H is rated for continuous service to 980°C (1,796 °F). It conducts heat at 15 W/m·K (8.67 BTU/hr·ft·°F), worse than 59% of stainless steel grades. Thermal expansion is 15.5 µm/m·K (8.61 µin/in·°F).
Electrical3
E309H conducts electricity at 2.2 % IACS, worse than 61% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (62/100), worse than 52% of stainless steel grades.
Sustainability4
Producing a kilogram of E309H takes about 68 MJ of energy and emits 5.2 kg of CO₂ — more than 80% of stainless steel grades. Typical recycled content is 60%.
Manufacturability7
E309H's machinability is poor (30/100, worse than 70% of stainless steel grades); weldability excellent (88/100); formability fair (45/100).
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. E309H is highlighted; hover a dot for its name, or open the interactive family chart.
Working with E309H
Is E309H easy to machine?
Weld deposits machine like Type 309 — gummy and work-hardening; use rigid setups, positive-rake carbide, heavy feeds and flood coolant, and expect ~35 % of 1212 rates.
Can E309H be welded?
Run stringer beads with low heat input, keep interpass below ~150 °C, redry basic electrodes at 300–350 °C, and target 8–15 FN to avoid hot cracking in dilution zones.
Can E309H be formed, bent or molded?
Not a wrought product form; deposited metal tolerates only limited cold straightening because ferrite plus high carbon reduce ductility after thermal exposure.
E309H 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 |
|---|---|---|
| Cthe 'H' requirement — raises high-temperature creep strength | 0.04 – 0.15 | 0.1 |
| Cr | 22 – 25 | 23.5 |
| Ni | 12 – 14 | 13 |
| Mn | 0.5 – 2.5 | 1.6 |
| Si0.30–0.65 % for ER309H bare wire per AWS A5.9 | ≤ 0.9 | 0.5 |
| Moresidual | ≤ 0.75 | 0.1 |
| Curesidual | ≤ 0.75 | 0.1 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.03 | 0.01 |
| Fe | balance |
What surface finishes work on E309H?
Remove slag and heat tint completely, then pickle/passivate (ASTM A380/A967) or blast with stainless grit; do not anodize — carbon steel media contamination causes rust bleeding.
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 E309H in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- ASTM
- A5.4
- Similar grades
- W30910
How much does E309H cost?
E309H 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.
E309H — frequently asked
What is E309H used for?
E309H is typically used for high-temperature dissimilar-metal joints, clad overlay on furnace and boiler components, stainless-to-carbon-steel transition welds in hot service, heat-treatment fixture and retort repair, buffer layers under high-temperature surfacing and petrochemical reformer and heater component welds. In short: high-temperature 309 electrode; creep-strength dissimilar filler; service to 980 °C.
What is the yield strength of E309H?
E309H has a typical yield strength of 420 MPa (60.9 ksi) and a tensile strength of 600 MPa (87 ksi) — stronger than 64% of stainless steel grades. Strength varies by condition: see the 5 listed tempers.
Is E309H easy to machine?
Not especially — machinability is rated poor (30/100, worse than 70% of stainless steel grades). Weld deposits machine like Type 309 — gummy and work-hardening; use rigid setups, positive-rake carbide, heavy feeds and flood coolant, and expect ~35 % of 1212 rates.
Can E309H be welded?
Yes — weldability is rated excellent (88/100). Run stringer beads with low heat input, keep interpass below ~150 °C, redry basic electrodes at 300–350 °C, and target 8–15 FN to avoid hot cracking in dilution zones.
What surface finishes work on E309H?
Remove slag and heat tint completely, then pickle/passivate (ASTM A380/A967) or blast with stainless grit; do not anodize — carbon steel media contamination causes rust bleeding.
Can E309H be formed, bent or molded?
Not a wrought product form; deposited metal tolerates only limited cold straightening because ferrite plus high carbon reduce ductility after thermal exposure.
What is the maximum service temperature of E309H?
E309H is rated for continuous use to about 980°C (1,796 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between E309H-AW and E309H PWHT?
AW is the default condition — default condition for E309H covered electrodes: dissimilar joints, clad restoration and 304H/309H/310H high-temperature service without PWHT. PWHT: applies when the Cr-Mo or carbon-steel side requires code PWHT; expect carbide precipitation and partial ferrite transformation with a toughness drop. Yield strength is 420 MPa in AW versus 390 MPa in PWHT.
How much does E309H cost?
E309H 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 A5.4/A5.4M — Stainless Steel Electrodes for Shielded Metal Arc Welding — American Welding Society (2012)
- AWS A5.9/A5.9M — Bare Stainless Steel Welding Electrodes and Rods — American Welding Society (2017)
- AWS A5.22 — Stainless Steel Flux Cored and Metal Cored Electrodes — American Welding Society (2012)
- ASM Handbook Vol. 6 — Welding, Brazing and Soldering — ASM International (1993)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels — ASM International (1990)
- Stainless SMAW/GTAW consumable datasheets (E309H / ER309H) — Böhler Welding / ESAB / Lincoln Electric (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.