Stainless Steel E310Mo
UNS W31020
E310Mo is a molybdenum-bearing 25Cr-20Ni austenitic electrode (UNS W31020) in the AWS A5.4 stainless SMAW family, supplied as -15 and -16 coatings and used as-welded or solution annealed.
Reference datasheet — E310Mo 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
E310Mo tempers and conditions
E310Mo is supplied in 4 conditions, soft to hard. AW is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed weld metal | Used when the fabrication receives a full solution anneal to dissolve carbides/σ-phase and restore maximum ductility and corrosion resistance; strength drops, elongation rises. | 290 | 540 | 45 | 160 HB | 2 % IACS |
Titania (rutile) covering, AC or DCEP | Choose the rutile-coated version for smoother arc, easy slag removal and better bead appearance in all-position work on AC or DCEP power sources. | 395 | 590 | 34 | 185 HB | 2 % IACS |
AWDefault As-welded deposit | Default condition: properties of the undiluted deposit in the as-welded state, no PWHT. | 400 | 595 | 35 | 185 HB | 2 % IACS |
Lime-basic covering, DCEP | Choose the basic-coated version for lowest hydrogen/oxygen, best toughness and crack resistance on restrained or thick joints; DC electrode-positive only. | 410 | 600 | 36 | 185 HB | 2 % IACS |
What is E310Mo?
E310Mo is a molybdenum-bearing 25Cr-20Ni austenitic electrode (UNS W31020) in the AWS A5.4 stainless SMAW family, supplied as -15 and -16 coatings and used as-welded or solution annealed. The molybdenum addition improves pitting and crevice resistance (corrosion resistance score 75) while retaining oxidation resistance to 1100 °C; typical as-welded values are 400 MPa yield, 595 MPa tensile, 35 % elongation and 185 HB (90 HRB). The deposit is ferrite-free and therefore hot-crack sensitive, and electrodes are stocked less widely than E310. Use plain E310 where service is oxidising rather than wet-corrosive. E310Mo 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). E310Mo has a yield strength of 400 MPa (58 ksi) and a tensile strength of 595 MPa (86.3 ksi) — stronger than 57% of stainless steel grades. Elongation at break is 35% and the elastic modulus is 200 GPa (29 Msi).
What is E310Mo used for?
- chemical process equipment
- high-temperature corrosive service
- flue gas equipment
Advantages
- High service temperature — 1,100°C (2,012 °F), better than 96% of stainless steel grades
- Good corrosion resistance — 75/100, better than 79% of stainless steel grades
Limitations
- High embodied carbon — 6 kg CO₂/kg, worse than 88% of stainless steel grades
- Low electrical conductivity — 2 % IACS, worse than 77% of stainless steel grades
E310Mo properties
Typical room-temperature values for E310Mo-AW; bars are the position among stainless steel grades.
Physical3
E310Mo 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
E310Mo has a yield strength of 400 MPa (58 ksi) and a tensile strength of 595 MPa (86.3 ksi) — stronger than 57% of stainless steel grades. Elongation at break is 35% and the elastic modulus is 200 GPa (29 Msi).
Thermal6
E310Mo is rated for continuous service to 1,100°C (2,012 °F). It conducts heat at 14.2 W/m·K (8.2 BTU/hr·ft·°F), worse than 76% of stainless steel grades. Thermal expansion is 15.5 µm/m·K (8.61 µin/in·°F).
Electrical3
E310Mo conducts electricity at 2 % IACS, worse than 77% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is very good (75/100), better than 79% of stainless steel grades.
Sustainability4
Producing a kilogram of E310Mo takes about 78 MJ of energy and emits 6 kg of CO₂ — more than 87% of stainless steel grades. Typical recycled content is 50%.
Manufacturability6
E310Mo's machinability is poor (28/100, worse than 79% 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. E310Mo is highlighted; hover a dot for its name, or open the interactive family chart.
Working with E310Mo
Is E310Mo easy to machine?
Fully austenitic and strongly work-hardening — grind or machine with sharp carbide tools, heavy positive rake, rigid setup and low speed/high feed; expect ~30 % of free-machining steel productivity.
Can E310Mo be welded?
SMAW with short arc, stringer beads, low heat input and interpass ≤150 °C to limit hot cracking in this ferrite-free deposit; redry electrodes (≈300 °C/1 h for -15, per maker for -16) and clean/limit dilution from the base metal.
Can E310Mo be formed, bent or molded?
Not a wrought product; the deposit is very ductile (≥30 % elongation) and can be peened or lightly dressed, but heavy cold work raises hardness fast.
E310Mo 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 | ≤ 0.12 | 0.1 |
| Cr | 25 – 28 | 26.5 |
| Ni | 20 – 22 | 21 |
| Mopitting/crevice resistance addition vs E310 | 2 – 3 | 2.5 |
| Mn | 1 – 2.5 | 1.8 |
| Si | ≤ 0.75 | 0.5 |
| P | ≤ 0.03 | 0.02 |
| S | ≤ 0.03 | 0.01 |
| Cu | ≤ 0.75 | 0.1 |
| Fe | balance |
What surface finishes work on E310Mo?
Remove slag fully, then pickle/passivate or mechanically blend and polish; avoid carbon-steel tooling contamination to preserve the passive film.
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 E310Mo in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- W31020
- Also called
- AWS A5.4 E310Mo
How much does E310Mo cost?
E310Mo 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.
E310Mo — frequently asked
What is E310Mo used for?
E310Mo is typically used for chemical process equipment, high-temperature corrosive service and flue gas equipment. In short: mo-alloyed 310 electrode; better pitting resistance than E310; service to 1100 °C.
What is the yield strength of E310Mo?
E310Mo has a typical yield strength of 400 MPa (58 ksi) and a tensile strength of 595 MPa (86.3 ksi) — stronger than 57% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.
Is E310Mo easy to machine?
Not especially — machinability is rated poor (28/100, worse than 79% of stainless steel grades). Fully austenitic and strongly work-hardening — grind or machine with sharp carbide tools, heavy positive rake, rigid setup and low speed/high feed; expect ~30 % of free-machining steel productivity.
Can E310Mo be welded?
Yes — weldability is rated good (60/100). SMAW with short arc, stringer beads, low heat input and interpass ≤150 °C to limit hot cracking in this ferrite-free deposit; redry electrodes (≈300 °C/1 h for -15, per maker for -16) and clean/limit dilution from the base metal.
What surface finishes work on E310Mo?
Remove slag fully, then pickle/passivate or mechanically blend and polish; avoid carbon-steel tooling contamination to preserve the passive film.
Can E310Mo be formed, bent or molded?
Not a wrought product; the deposit is very ductile (≥30 % elongation) and can be peened or lightly dressed, but heavy cold work raises hardness fast.
What is the maximum service temperature of E310Mo?
E310Mo 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 E310Mo-AW and E310Mo-SA?
AW is the default condition — default condition: properties of the undiluted deposit in the as-welded state, no PWHT. SA: used when the fabrication receives a full solution anneal to dissolve carbides/σ-phase and restore maximum ductility and corrosion resistance; strength drops, elongation rises. Yield strength is 400 MPa in AW versus 290 MPa in SA.
How much does E310Mo cost?
E310Mo 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 Specification for Stainless Steel Electrodes for Shielded Metal Arc Welding — American Welding Society (2012)
- ASM Handbook Vol.6 — Welding, Brazing and Soldering — ASM International (1993)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels, and High-Performance Alloys — ASM International (1990)
- ASM Handbook Vol.13B — Corrosion: Materials — ASM International (2005)
- Stainless SMAW electrode datasheets (E310/E310Mo class) — 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.