Stainless Steel E308Mo-AW (As-welded deposit)
Heat-treated state · default condition
UNS W30820 · ASTM A5.4
Default condition for all austenitic stainless SMAW deposits; use for normal fabrication where no PWHT is applied.
Values for the AW condition
Other E308Mo tempers and conditions
E308Mo is listed in 5 conditions; see the grade overview at E308Mo.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution Annealed (~1050 °C, water quenched) deposit | Use when the weldment is solution annealed after welding (e.g. clad or overlay parts) to dissolve carbides and restore full intergranular corrosion resistance; strength drops and ferrite is largely retained but redistributed. | 300 | 550 | 45 | 160 HB | 2.4 % IACS |
AWDefaultThis page As-welded deposit | Default condition for all austenitic stainless SMAW deposits; use for normal fabrication where no PWHT is applied. | 420 | 590 | 38 | 180 HB | 2.3 % IACS |
E308Mo-15 | Pick when the lowest hydrogen/highest deposit toughness and best out-of-position root running are needed; DC electrode positive only. | 420 | 585 | 40 | 175 HB | 2.3 % IACS |
E308Mo-16 | Most widely stocked coating type; smooth arc, easy slag removal and good bead appearance on AC or DC transformers. | 420 | 590 | 38 | 180 HB | 2.3 % IACS |
E308Mo-17 | Higher-silica rutile variant giving a flatter, wider bead and better wash-in for fillets and horizontal work. | 430 | 600 | 36 | 185 HB | 2.3 % IACS |
What is E308Mo-AW?
E308Mo-AW is E308Mo heat treated to AW — default condition for all austenitic stainless SMAW deposits; use for normal fabrication where no PWHT is applied. E308Mo-AW has a yield strength of 420 MPa (60.9 ksi) and a tensile strength of 590 MPa (85.6 ksi) — stronger than 64% of stainless steel grades. Elongation at break is 38% and the elastic modulus is 193 GPa (28 Msi). E308Mo-AW 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).
Advantages
- Readily welded — 90/100, better than 95% of stainless steel grades
Limitations
- High embodied carbon — 5.5 kg CO₂/kg, worse than 77% of stainless steel grades
E308Mo-AW properties
Typical room-temperature values for E308Mo-AW; 23 are specific to this condition. Other listed values are E308Mo reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
E308Mo-AW 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
E308Mo-AW has a yield strength of 420 MPa (60.9 ksi) and a tensile strength of 590 MPa (85.6 ksi) — stronger than 64% of stainless steel grades. Elongation at break is 38% and the elastic modulus is 193 GPa (28 Msi).
Thermal6
E308Mo-AW is rated for continuous service to 650°C (1,202 °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 16.5 µm/m·K (9.17 µin/in·°F).
Electrical3
E308Mo-AW conducts electricity at 2.3 % IACS, better than 55% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is good (66/100), better than 59% of stainless steel grades.
Sustainability4
Producing a kilogram of E308Mo-AW takes about 55 MJ of energy and emits 5.5 kg of CO₂ — more than 50% of stainless steel grades. Typical recycled content is 60%.
Manufacturability7
E308Mo-AW's machinability is fair (38/100, better than 63% of stainless steel grades); weldability excellent (90/100); formability good (60/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with E308Mo-AW
Is E308Mo easy to machine?
Weld deposit work-hardens rapidly — use sharp carbide tools, positive rake, heavy feeds and flood coolant; grinding of caps is usually easier than machining.
Can E308Mo be welded?
SMAW with DCEP (AC also for -16/-17); keep interpass below ~150 °C, use stringer beads, no preheat, redry electrodes at 250–300 °C to avoid porosity.
Can E308Mo be formed, bent or molded?
Deposited metal is ductile but strain-hardens quickly; avoid heavy cold straightening across weld beads.
What surface finishes work on E308Mo?
Pickle and passivate (ASTM A380/A967) after welding to remove heat tint; ferrite stringers can show as faint lines after polishing.
E308Mo 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 |
|---|---|---|
| Cstandard carbon grade | ≤ 0.08 | 0.05 |
| Cr | 18 – 21 | 19.5 |
| Ni | 9 – 12 | 10.5 |
| Mopitting resistance addition vs E308 | 2 – 3 | 2.5 |
| 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 | 0.15 |
| Fe | balance | — |
E308Mo-AW — frequently asked
What is E308Mo-AW used for?
E308Mo-AW is typically used for mixed 304/316 fabrications, moderate chloride service and general stainless piping. In short: mo-boosted 308 electrode; bridges 304 and 316; better pitting than E308.
What is the yield strength of E308Mo-AW?
E308Mo-AW has a typical yield strength of 420 MPa (60.9 ksi) and a tensile strength of 590 MPa (85.6 ksi) — stronger than 64% of stainless steel grades. Strength varies by condition: see the 5 listed tempers.
Is E308Mo-AW easy to machine?
Not especially — machinability is rated fair (38/100, better than 63% of stainless steel grades). Weld deposit work-hardens rapidly — use sharp carbide tools, positive rake, heavy feeds and flood coolant; grinding of caps is usually easier than machining.
Can E308Mo-AW be welded?
Yes — weldability is rated excellent (90/100). SMAW with DCEP (AC also for -16/-17); keep interpass below ~150 °C, use stringer beads, no preheat, redry electrodes at 250–300 °C to avoid porosity.
What surface finishes work on E308Mo-AW?
Pickle and passivate (ASTM A380/A967) after welding to remove heat tint; ferrite stringers can show as faint lines after polishing.
Can E308Mo-AW be formed, bent or molded?
Deposited metal is ductile but strain-hardens quickly; avoid heavy cold straightening across weld beads.
What is the maximum service temperature of E308Mo-AW?
E308Mo-AW is rated for continuous use to about 650°C (1,202 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between E308Mo-AW and E308Mo SOL-ANN?
AW is the default condition — default condition for all austenitic stainless SMAW deposits; use for normal fabrication where no PWHT is applied. SOL-ANN: use when the weldment is solution annealed after welding (e.g. clad or overlay parts) to dissolve carbides and restore full intergranular corrosion resistance; strength drops and ferrite is largely retained but redistributed. Yield strength is 420 MPa in AW versus 300 MPa in SOL-ANN.
Sources
- AWS A5.4/A5.4M — Specification for Stainless Steel Electrodes for Shielded Metal Arc Welding — American Welding Society (2012)
- ASME BPVC Section II Part C SFA-5.4 — ASME (2023)
- 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)
- Stainless SMAW electrode all-weld-metal datasheets (308/308Mo types) — Böhler Welding / ESAB / Lincoln Electric (2023)
Property data is compiled from published supplier and standards handbooks and normalised for comparison. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.