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Stainless Steel Alloy 611 Annealed

Temper · default condition

UNS S30601

Standard supply condition for all corrosion service — maximum ductility and a fully solutionized, film-forming surface.

High cost $$$$

Values for the Annealed 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 datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
AnnealedDefaultThis page
solution annealed and pickled (plate, sheet, tube, pipe)
Standard supply condition for all corrosion service — maximum ductility and a fully solutionized, film-forming surface.33065045190 HB—
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.35064030200 HB1.8 % 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.5608002524 HRC1.8 % 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).6008602025 HRC1.8 % IACS

What is Alloy 611 Annealed?

Alloy 611 Annealed is Alloy 611 in the Annealed temper — standard supply condition for all corrosion service — maximum ductility and a fully solutionized, film-forming surface. Alloy 611 Annealed has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 650 MPa (94.3 ksi) — weaker than 57% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 190 GPa (27.6 Msi). Alloy 611 Annealed 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).

Advantages

  • Ductile — tolerates forming and impact — 45%, better than 76% of stainless steel grades
  • Forms and bends easily — 68/100, better than 75% of stainless steel grades

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 Annealed properties

Typical room-temperature values for Alloy 611 Annealed; 11 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 Annealed 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).

Density7.6 g/cm³0.27 lb/in³
Melting Point (Solidus)1,350°C2,462 °F
Liquidus Temperature1,410°C2,570 °F

Mechanical13

Alloy 611 Annealed has a yield strength of 330 MPa (47.9 ksi) and a tensile strength of 650 MPa (94.3 ksi) — weaker than 57% of stainless steel grades. Elongation at break is 45% and the elastic modulus is 190 GPa (27.6 Msi).

Elastic (Young's) Modulus190 GPa27.6 Msi
Shear Modulus73 GPa10.6 Msi
Bulk Modulus158 GPa22.9 Msi
Poisson's Ratio0.3
Tensile Strength (Ultimate)650 MPa94.3 ksi
Yield Strength (0.2% offset)330 MPa47.9 ksi
Elongation at Break45%
Shear Strength420 MPa60.9 ksi
Fatigue Strength (Endurance Limit)270 MPa39.2 ksi
Charpy V-Notch Impact (RT)90 J66.4 ft·lbf
Hardness, Brinell190 HB
Hardness, Rockwell B90 HRB
Hardness, Vickers200 HV

Thermal5

Alloy 611 Annealed is rated for continuous service to 800°C (1,472 °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).

Thermal Conductivity12 W/m·K6.9 BTU/hr·ft·°F
Specific Heat Capacity500 J/kg·K0.12 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)15.5 µm/m·K8.6 µin/in·°F
Max Service Temperature (continuous)800°C1,472 °F
Min Service Temperature-100°C-148 °F

Electrical2

Alloy 611 Annealed has an electrical resistivity of 9.5×10⁻⁷ Ω·m.

Electrical Resistivity9.5×10⁻⁷ Ω·m37.4 µΩ·in
Magnetic Responsenon-magnetic

Chemical & Environmental3

Corrosion resistance is very good (72/100), better than 73% of stainless steel grades.

Galvanic Potential (seawater, vs SCE)-0.1 V
Corrosion ResistanceVery good72/100
Chemical Resistance SummaryExcellent in hot concentrated (>85 %) and mid-concentration sulfuric acid where the Si-rich passive film forms; good in nitric and other oxidizing acids; poor in dilute/reducing sulfuric, hydrochloric and hydrofluoric acid, and only moderate chloride pitting/crevice resistance because Mo is ≤0.2 %. Film is velocity-sensitive — keep flow low and avoid erosive slurries.

Sustainability4

Producing a kilogram of Alloy 611 Annealed takes about 62 MJ of energy and emits 6 kg of CO₂ — more than 75% of stainless steel grades. Typical recycled content is 45%.

Embodied Energy (primary production)62 MJ/kg26,655 BTU/lb
Embodied Carbon (primary production)6 kg CO₂/kg
Embodied Water180 L/kg21.6 gal/lb
Typical Recycled Content45%

Manufacturability7

Alloy 611 Annealed's machinability is poor (30/100, worse than 70% of stainless steel grades); weldability good (60/100); formability good (68/100).

MachinabilityPoor30/100
Machinability Rating (AISI 1212 = 100 %)35%
WeldabilityGood60/100
Formability (cold)Good68/100
Brazeability / SolderabilityFair45/100
PolishabilityVery good70/100
Anodizing Responsen/a — not an anodizing alloy; supplied pickled/bright annealed

Common Calculations5

Specific Strength (UTS / density)calculated86 kN·m/kg
Specific Stiffness (E / density)calculated25 MN·m/kg
Modulus of Resiliencecalculated287 kJ/m³
Thermal Diffusivitycalculated3.2 mm²/s
Thermal Shock Resistance Indexcalculated3

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with Alloy 611 Annealed

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.

ElementSpec limit (wt %)Nominal
Clow carbon to avoid sensitization≤ 0.020.01
Sikey element for the sulfuric-acid passive film5 – 5.65.3
Mn0.4 – 10.6
P≤ 0.03—
S≤ 0.01—
Cr17 – 1817.5
Nihigh Ni stabilizes austenite against the ferritizing effect of Si17 – 1817.5
Moresidual only — limits chloride pitting resistance≤ 0.20.1
Cu≤ 0.35—
Febalance—

Alloy 611 Annealed — frequently asked

What is Alloy 611 Annealed used for?

Alloy 611 Annealed 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 Annealed?

Alloy 611 Annealed has a typical yield strength of 330 MPa (47.9 ksi) and a tensile strength of 650 MPa (94.3 ksi) — weaker than 57% of stainless steel grades. Strength varies by condition: see the 4 listed tempers.

Is Alloy 611 Annealed easy to machine?

Not especially — machinability is rated poor (30/100, worse than 70% 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 Annealed be welded?

Yes — weldability is rated good (60/100). 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 Annealed?

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 Annealed 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 Annealed?

Alloy 611 Annealed 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 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

  1. ASTM A240/A240M — Chromium and Chromium-Nickel Stainless Steel Plate, Sheet and Strip — ASTM International (2023)
  2. ASTM A249/A269 — Welded and Seamless Austenitic Stainless Steel Tubing — ASTM International (2022)
  3. SAE/ASTM DS-56 (Metals & Alloys in the Unified Numbering System) — UNS S30601 — SAE International / ASTM (2017)
  4. High-silicon austenitic stainless steel for concentrated sulfuric acid (S30601 grade datasheet) — Sandvik Materials Technology / Alleima (2022)
  5. 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.