Stainless Steel Alloy 611-AW (As-welded deposit)
Heat-treated state
UNS S30601
Condition of welded pipe/tube seams and site welds; expect slightly lower ductility and use over-alloyed or matching high-Si filler plus post-weld pickling for full acid resistance.
Values for the AW condition
Other Alloy 611 tempers and conditions
Alloy 611 is listed in 4 conditions; see the grade overview at Alloy 611.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
AnnealedDefault solution annealed and pickled (plate, sheet, tube, pipe) | Standard supply condition for all corrosion service — maximum ductility and a fully solutionized, film-forming surface. | 330 | 650 | 45 | 190 HB | — |
AWThis page As-welded deposit | Condition of welded pipe/tube seams and site welds; expect slightly lower ductility and use over-alloyed or matching high-Si filler plus post-weld pickling for full acid resistance. | 350 | 640 | 30 | 200 HB | 1.8 % IACS |
Cold drawn | Bar/wire form for fasteners, spray nozzles and machined acid-plant fittings; anneal after heavy drawing if full corrosion performance is required. | 560 | 800 | 25 | 24 HRC | 1.8 % IACS |
1/4 Hard | Use only where extra stiffness/strength is needed and the part will not see high-stress acid service (SCC and film-forming behaviour favour the annealed state). | 600 | 860 | 20 | 25 HRC | 1.8 % IACS |
What is Alloy 611-AW?
Alloy 611-AW is Alloy 611 heat treated to AW — condition of welded pipe/tube seams and site welds; expect slightly lower ductility and use over-alloyed or matching high-Si filler plus post-weld pickling for full acid resistance. Alloy 611-AW has a yield strength of 350 MPa (50.8 ksi) and a tensile strength of 640 MPa (92.8 ksi) — weaker than 52% of stainless steel grades. Elongation at break is 30% and the elastic modulus is 190 GPa (27.6 Msi). Alloy 611-AW has a density of 7.6 g/cm³ (0.275 lb/in³), lighter than 98% of stainless steel grades. It melts at 1,350°C (2,462 °F). Annealed is the default condition FabDigit quotes; AW is available on request or by drawing note.
Limitations
- Poor heat conductor — 12 W/m·K (6.93 BTU/hr·ft·°F), worse than 93% of stainless steel grades
- High embodied carbon — 6 kg CO₂/kg, worse than 88% of stainless steel grades
Alloy 611-AW properties
Typical room-temperature values for Alloy 611-AW; 22 are specific to this condition. Other listed values are Alloy 611 reference data and may not represent this condition. Bars are the position among stainless steel grades.
Physical3
Alloy 611-AW has a density of 7.6 g/cm³ (0.275 lb/in³), lighter than 98% of stainless steel grades. It melts at 1,350°C (2,462 °F).
Mechanical13
Alloy 611-AW has a yield strength of 350 MPa (50.8 ksi) and a tensile strength of 640 MPa (92.8 ksi) — weaker than 52% of stainless steel grades. Elongation at break is 30% and the elastic modulus is 190 GPa (27.6 Msi).
Thermal5
Alloy 611-AW is rated for continuous service to 750°C (1,382 °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 15.5 µm/m·K (8.61 µin/in·°F).
Electrical2
Alloy 611-AW has an electrical resistivity of 9.6×10⁻⁷ Ω·m.
Chemical & Environmental3
Corrosion resistance is good (66/100), better than 59% of stainless steel grades.
Sustainability4
Producing a kilogram of Alloy 611-AW takes about 62 MJ of energy and emits 6 kg of CO₂ — more than 75% of stainless steel grades. Typical recycled content is 45%.
Manufacturability7
Alloy 611-AW's machinability is poor (27/100, worse than 83% of stainless steel grades); weldability good (58/100); formability fair (45/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Alloy 611-AW
Is Alloy 611 easy to machine?
Treat as a tough, abrasive austenitic: rigid setups, sharp coated carbide, positive rake, 20–35 % lower speed than 304, heavy flood coolant, avoid dwell to prevent work hardening.
Can Alloy 611 be welded?
GTAW/GMAW/SAW with matching high-Si or over-alloyed austenitic filler, low heat input, no preheat, interpass below ~150 °C; keep dilution low and pickle/passivate the weld zone before acid service.
Can Alloy 611 be formed, bent or molded?
Cold forms like a high-work-hardening austenitic — allow generous bend radii, extra springback and intermediate annealing (1050–1120 °C, rapid cool) for severe drawing; hot work 900–1150 °C.
What surface finishes work on Alloy 611?
Pickle in nitric/HF or nitric-based passivating bath to remove the silica-rich scale after welding or annealing; mechanical polishing works well, no anodizing or plating normally used.
Alloy 611 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 to avoid sensitization | ≤ 0.02 | 0.01 |
| Sikey element for the sulfuric-acid passive film | 5 – 5.6 | 5.3 |
| Mn | 0.4 – 1 | 0.6 |
| P | ≤ 0.03 | — |
| S | ≤ 0.01 | — |
| Cr | 17 – 18 | 17.5 |
| Nihigh Ni stabilizes austenite against the ferritizing effect of Si | 17 – 18 | 17.5 |
| Moresidual only — limits chloride pitting resistance | ≤ 0.2 | 0.1 |
| Cu | ≤ 0.35 | — |
| Fe | balance | — |
Alloy 611-AW — frequently asked
What is Alloy 611-AW used for?
Alloy 611-AW is typically used for high-temperature furnace components, petrochemical process tubing, furnace retorts in sulfidising atmospheres, radiant tubes, carburizing furnace fixtures and reformer and heater hardware. In short: sulfidation-resistant 310 variant; molybdenum-modified heat-resistant grade; tougher to machine than 304.
What is the yield strength of Alloy 611-AW?
Alloy 611-AW has a typical yield strength of 350 MPa (50.8 ksi) and a tensile strength of 640 MPa (92.8 ksi) — weaker than 52% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.
Is Alloy 611-AW easy to machine?
Not especially — machinability is rated poor (27/100, worse than 83% of stainless steel grades). Treat as a tough, abrasive austenitic: rigid setups, sharp coated carbide, positive rake, 20–35 % lower speed than 304, heavy flood coolant, avoid dwell to prevent work hardening.
Can Alloy 611-AW be welded?
Yes — weldability is rated good (58/100). GTAW/GMAW/SAW with matching high-Si or over-alloyed austenitic filler, low heat input, no preheat, interpass below ~150 °C; keep dilution low and pickle/passivate the weld zone before acid service.
What surface finishes work on Alloy 611-AW?
Pickle in nitric/HF or nitric-based passivating bath to remove the silica-rich scale after welding or annealing; mechanical polishing works well, no anodizing or plating normally used.
Can Alloy 611-AW be formed, bent or molded?
Cold forms like a high-work-hardening austenitic — allow generous bend radii, extra springback and intermediate annealing (1050–1120 °C, rapid cool) for severe drawing; hot work 900–1150 °C.
What is the maximum service temperature of Alloy 611-AW?
Alloy 611-AW is rated for continuous use to about 750°C (1,382 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Alloy 611 Annealed and Alloy 611-CD?
Annealed is the default condition — standard supply condition for all corrosion service — maximum ductility and a fully solutionized, film-forming surface. CD: bar/wire form for fasteners, spray nozzles and machined acid-plant fittings; anneal after heavy drawing if full corrosion performance is required. Yield strength is 330 MPa in Annealed versus 560 MPa in CD.
Sources
- ASTM A240/A240M — Chromium and Chromium-Nickel Stainless Steel Plate, Sheet and Strip — ASTM International (2023)
- ASTM A249/A269 — Welded and Seamless Austenitic Stainless Steel Tubing — ASTM International (2022)
- SAE/ASTM DS-56 (Metals & Alloys in the Unified Numbering System) — UNS S30601 — SAE International / ASTM (2017)
- High-silicon austenitic stainless steel for concentrated sulfuric acid (S30601 grade datasheet) — Sandvik Materials Technology / Alleima (2022)
- ASM Handbook Vol.13B — Corrosion: Materials (sulfuric acid service) — ASM International (2005)
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.