Stainless Steel E33-31-AW (As-welded deposit)
Heat-treated state · default condition
UNS W33310
Standard stocked condition: covered-electrode deposit used in the as-welded state for acid-service fabrication and repair.
Values for the AW condition
Other E33-31 tempers and conditions
E33-31 is listed in 3 conditions; see the grade overview at E33-31.
Compare all 3 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Weldment solution annealed ~1120–1180 °C and quenched | Choose when the fabricated component can be re-solution-annealed to dissolve interdendritic precipitates and restore maximum ductility and acid resistance. | 410 | 790 | 45 | 210 HB | 1.9 % IACS |
AWDefaultThis page As-welded deposit | Standard stocked condition: covered-electrode deposit used in the as-welded state for acid-service fabrication and repair. | 480 | 760 | 33 | 21 HRC | 1.9 % IACS |
AW-GTAW/GMAW | Pick for root passes, thin-wall and high-purity acid-service welds where the cleaner, slightly tougher bare-wire deposit is required. | 500 | 780 | 38 | 225 HB | 1.9 % IACS |
What is E33-31-AW?
E33-31-AW is E33-31 heat treated to AW — standard stocked condition: covered-electrode deposit used in the as-welded state for acid-service fabrication and repair. E33-31-AW has a yield strength of 480 MPa (69.6 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 75% of stainless steel grades. Elongation at break is 33% and the elastic modulus is 196 GPa (28.4 Msi). E33-31-AW has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 68% of stainless steel grades. It melts at 1,350°C (2,462 °F).
Advantages
- Good corrosion resistance — 88/100, better than 97% of stainless steel grades
- High strength — 480 MPa (69.6 ksi), better than 75% of stainless steel grades
Limitations
- Difficult to machine — 20/100, worse than 98% of stainless steel grades
- Poor heat conductor — 12 W/m·K (6.93 BTU/hr·ft·°F), worse than 93% of stainless steel grades
- High embodied carbon — 6.5 kg CO₂/kg, worse than 93% of stainless steel grades
- Low electrical conductivity — 1.9 % IACS, worse than 84% of stainless steel grades
E33-31-AW properties
Typical room-temperature values for E33-31-AW; 23 are specific to this condition. Other listed values are E33-31 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
E33-31-AW has a density of 7.9 g/cm³ (0.285 lb/in³), heavier than 68% of stainless steel grades. It melts at 1,350°C (2,462 °F).
Mechanical16
E33-31-AW has a yield strength of 480 MPa (69.6 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 75% of stainless steel grades. Elongation at break is 33% and the elastic modulus is 196 GPa (28.4 Msi).
Thermal6
E33-31-AW is rated for continuous service to 550°C (1,022 °F). It conducts heat at 12 W/m·K (6.93 BTU/hr·ft·°F), worse than 93% of stainless steel grades. Thermal expansion is 14.5 µm/m·K (8.06 µin/in·°F).
Electrical3
E33-31-AW conducts electricity at 1.9 % IACS, worse than 84% of stainless steel grades.
Chemical & Environmental3
Corrosion resistance is excellent (88/100), better than 97% of stainless steel grades.
Sustainability4
Producing a kilogram of E33-31-AW takes about 90 MJ of energy and emits 6.5 kg of CO₂ — more than 94% of stainless steel grades. Typical recycled content is 30%.
Manufacturability7
E33-31-AW's machinability is poor (20/100, worse than 98% of stainless steel grades); weldability very good (70/100); formability fair (40/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with E33-31-AW
Is E33-31 easy to machine?
Very poor machinability — high N content gives severe work hardening; use rigid setups, sharp positive-rake carbide, low speed with heavy positive feed and flood coolant.
Can E33-31 be welded?
Weld with low heat input, stringer beads and interpass temperature below ~120 °C; keep electrodes dry (re-bake per producer instruction) and use Ar or Ar+He shielding — avoid N-free backing gas losses and never use oxidising/CO₂-rich mixtures.
Can E33-31 be formed, bent or molded?
Deposit is strong and heavily work hardening; cold straightening of wire/weldment is limited — prefer solution annealing before any significant cold work.
What surface finishes work on E33-31?
Grind off all weld oxide/tint, then pickle and passivate (HNO₃-HF type) to restore the Cr-rich passive film before acid service; can be polished to a bright finish.
E33-31 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 |
|---|---|---|
| Clow carbon for acid service | ≤ 0.02 | 0.01 |
| Cr | 31 – 35 | 33 |
| Ni | 30 – 33 | 31 |
| Mo | 0.5 – 2 | 1.6 |
| Cuaids sulfuric acid resistance | 0.3 – 1.2 | 0.6 |
| Naustenite stabiliser and strengthener | 0.3 – 0.6 | 0.4 |
| Mn | ≤ 2 | 0.6 |
| Si | ≤ 0.8 | 0.4 |
| P | ≤ 0.02 | — |
| S | ≤ 0.01 | — |
| Febalance, approx. 30 % | balance | — |
E33-31-AW — frequently asked
What is E33-31-AW used for?
E33-31-AW is typically used for phosphoric acid production, sulfuric acid dew-point equipment and super-austenitic pressure vessels. In short: strongest deposit in family; super-austenitic acid resistance; poor machinability.
What is the yield strength of E33-31-AW?
E33-31-AW has a typical yield strength of 480 MPa (69.6 ksi) and a tensile strength of 760 MPa (110 ksi) — stronger than 75% of stainless steel grades. Strength varies by condition: see the 3 listed tempers.
Is E33-31-AW easy to machine?
Not especially — machinability is rated poor (20/100, worse than 98% of stainless steel grades). Very poor machinability — high N content gives severe work hardening; use rigid setups, sharp positive-rake carbide, low speed with heavy positive feed and flood coolant.
Can E33-31-AW be welded?
Yes — weldability is rated very good (70/100). Weld with low heat input, stringer beads and interpass temperature below ~120 °C; keep electrodes dry (re-bake per producer instruction) and use Ar or Ar+He shielding — avoid N-free backing gas losses and never use oxidising/CO₂-rich mixtures.
What surface finishes work on E33-31-AW?
Grind off all weld oxide/tint, then pickle and passivate (HNO₃-HF type) to restore the Cr-rich passive film before acid service; can be polished to a bright finish.
Can E33-31-AW be formed, bent or molded?
Deposit is strong and heavily work hardening; cold straightening of wire/weldment is limited — prefer solution annealing before any significant cold work.
What is the maximum service temperature of E33-31-AW?
E33-31-AW is rated for continuous use to about 550°C (1,022 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between E33-31-AW and E33-31-SA?
AW is the default condition — standard stocked condition: covered-electrode deposit used in the as-welded state for acid-service fabrication and repair. SA: choose when the fabricated component can be re-solution-annealed to dissolve interdendritic precipitates and restore maximum ductility and acid resistance. Yield strength is 480 MPa in AW versus 410 MPa in SA.
Sources
- AWS A5.4/A5.4M — Specification for 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)
- ASTM B625 / A240 (UNS R20033 requirements) — ASTM International (2021)
- VDM Alloy 33 (Nicrofer 3033) material data sheet — VDM Metals (2018)
- ASM Handbook Vol. 6 — Welding, Brazing and Soldering (stainless filler metals) — ASM International (1993)
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.