Stainless Steel E318
EN E318 · UNS W31910
E318 is a niobium-stabilized 316-type (W31910) covered electrode — the 316Cb member of the austenitic stainless filler family — pairing molybdenum for pitting resistance with Nb stabilization against chromium carbide precipitation.
Reference datasheet — E318 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
E318 tempers and conditions
E318 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 | Used when the fabrication is stabilizing-annealed with the base metal; softens the deposit and lowers ferrite slightly. | 360 | 560 | 40 | 165 HB | 2.3 % IACS |
Silica-titania coating, AC or DCEP, higher deposition | Choose for flat/horizontal fillets where bead appearance and deposition rate matter; slightly more fluid slag than -16. | 410 | 580 | 36 | 178 HB | 2.2 % IACS |
AWDefault As-welded deposit | Standard supply/qualification condition: properties of the deposit as deposited, tested per AWS A5.4. | 415 | 590 | 35 | 180 HB | 2.2 % IACS |
Titania (rutile) coating, AC or DCEP, all positions | Most widely stocked type: smooth arc, easy slag release, AC-capable — general fabrication of 316Cb/316Ti. | 415 | 590 | 35 | 180 HB | 2.2 % IACS |
Lime (basic) coating, DCEP, all positions | Pick for root passes, restrained joints and best low-temperature/impact toughness; DC only, slightly rougher bead. | 420 | 585 | 36 | 180 HB | 2.2 % IACS |
What is E318?
E318 is a niobium-stabilized 316-type (W31910) covered electrode — the 316Cb member of the austenitic stainless filler family — pairing molybdenum for pitting resistance with Nb stabilization against chromium carbide precipitation. It is chosen for matching welds on stabilized Mo-bearing stainless in petrochemical and high-temperature piping, and is supplied as -15, -16 and -17 coated electrodes. Typical deposit values are 415 MPa yield, 590 MPa tensile, 35 % elongation and 180 HB (89 HRB), with service to 800 °C. Where stabilization is not required, E316L is cheaper and more widely stocked. E318 has a density of 7.96 g/cm³ (0.288 lb/in³), heavier than 83% of stainless steel grades. It melts at 1,375°C (2,507 °F). E318 has a yield strength of 415 MPa (60.2 ksi) and a tensile strength of 590 MPa (85.6 ksi) — stronger than 62% of stainless steel grades. Elongation at break is 35% and the elastic modulus is 190 GPa (27.6 Msi).
What is E318 used for?
- high-temperature stabilized piping
- petrochemical equipment
- stabilized stainless fabrication
Advantages
- Readily welded — 88/100, better than 91% of stainless steel grades
E318 properties
Typical room-temperature values for E318-AW; bars are the position among stainless steel grades.
Physical3
E318 has a density of 7.96 g/cm³ (0.288 lb/in³), heavier than 83% of stainless steel grades. It melts at 1,375°C (2,507 °F).
Mechanical16
E318 has a yield strength of 415 MPa (60.2 ksi) and a tensile strength of 590 MPa (85.6 ksi) — stronger than 62% of stainless steel grades. Elongation at break is 35% and the elastic modulus is 190 GPa (27.6 Msi).
Thermal6
E318 is rated for continuous service to 800°C (1,472 °F). It conducts heat at 16 W/m·K (9.24 BTU/hr·ft·°F), better than 58% of stainless steel grades. Thermal expansion is 16 µm/m·K (8.89 µin/in·°F).
Electrical3
E318 conducts electricity at 2.2 % IACS, worse than 61% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is very good (72/100), better than 73% of stainless steel grades.
Sustainability4
Producing a kilogram of E318 takes about 55 MJ of energy and emits 5 kg of CO₂ — more than 50% of stainless steel grades. Typical recycled content is 55%.
Manufacturability7
E318'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. E318 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with E318
Is E318 easy to machine?
Deposit machines like 316: low speed, heavy positive-rake carbide, rigid setup and flood coolant to avoid work hardening; grind slag inclusions out first.
Can E318 be welded?
SMAW with short arc, stringer beads, interpass ≤150 °C and no preheat; redry electrodes 250–300 °C/1 h and keep hot to avoid porosity and moisture pickup.
Can E318 be formed, bent or molded?
Not a wrought product — deposit is ductile (≈35 % elongation) and tolerates weld-joint straightening, but heavy cold work raises hardness quickly.
E318 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 |
|---|---|---|
| CAWS A5.4 undiluted weld metal | ≤ 0.08 | 0.05 |
| Cr | 17 – 20 | 18.5 |
| Ni | 11 – 14 | 12 |
| Mo | 2 – 3 | 2.5 |
| NbNb+Ta, min = 6×C | 0.48 – 1 | 0.7 |
| Mn | 0.5 – 2.5 | 1.4 |
| Si | ≤ 0.9 | 0.6 |
| P | ≤ 0.04 | 0.02 |
| S | ≤ 0.03 | 0.01 |
| Cu | ≤ 0.75 | 0.1 |
| Fe | balance |
What surface finishes work on E318?
Remove all slag, then pickle/passivate (HNO₃-HF or citric per ASTM A967) or blast with stainless-only media to restore the passive film; electropolishing gives best chloride 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 E318 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- W31910
- Also called
- AWS A5.4 E318
How much does E318 cost?
E318 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.
E318 — frequently asked
What is E318 used for?
E318 is typically used for high-temperature stabilized piping, petrochemical equipment and stabilized stainless fabrication. In short: stabilized 316-type deposit; service to 800 °C; nb-stabilized alternative to E316L.
What is the yield strength of E318?
E318 has a typical yield strength of 415 MPa (60.2 ksi) and a tensile strength of 590 MPa (85.6 ksi) — stronger than 62% of stainless steel grades. Strength varies by condition: see the 5 listed tempers.
Is E318 easy to machine?
Not especially — machinability is rated poor (30/100, worse than 70% of stainless steel grades). Deposit machines like 316: low speed, heavy positive-rake carbide, rigid setup and flood coolant to avoid work hardening; grind slag inclusions out first.
Can E318 be welded?
Yes — weldability is rated excellent (88/100). SMAW with short arc, stringer beads, interpass ≤150 °C and no preheat; redry electrodes 250–300 °C/1 h and keep hot to avoid porosity and moisture pickup.
What surface finishes work on E318?
Remove all slag, then pickle/passivate (HNO₃-HF or citric per ASTM A967) or blast with stainless-only media to restore the passive film; electropolishing gives best chloride performance.
Can E318 be formed, bent or molded?
Not a wrought product — deposit is ductile (≈35 % elongation) and tolerates weld-joint straightening, but heavy cold work raises hardness quickly.
What is the maximum service temperature of E318?
E318 is rated for continuous use to about 800°C (1,472 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between E318-AW and E318 PWHT?
AW is the default condition — standard supply/qualification condition: properties of the deposit as deposited, tested per AWS A5.4. PWHT: used when the fabrication is stabilizing-annealed with the base metal; softens the deposit and lowers ferrite slightly. Yield strength is 415 MPa in AW versus 360 MPa in PWHT.
How much does E318 cost?
E318 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)
- GB/T 983 — (stainless steel covered electrodes) — SAC (2012)
- ASM Handbook Vol. 6 — Welding, Brazing and Soldering — ASM International (1993)
- ASM Handbook Vol. 13B — Corrosion: Materials — ASM International (2005)
- 316Cb / E318 covered electrode all-weld-metal data — Böhler Welding / ESAB (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.