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Nickel Alloy Hastelloy G-AW (As-welded deposit)

Heat-treated state

UNS N06007, N06920 · EN 2.4618

Weld metal / as-welded joint properties for fabricated vessels; solution anneal after welding where sensitization is a concern.

High cost $$$$

Values for the AW condition

Other Hastelloy G tempers and conditions

Hastelloy G is listed in 5 conditions; see the grade overview at Hastelloy G.

Compare all 5 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
Hot Worked / Hot Finished
Heavy bar, ring and forging sections where hot working is followed by solution anneal; slightly lower strength scatter than cold work.30067050175 HB1.5 % IACS
ANNDefault
Annealed
Standard stocked condition for plate, sheet, tube and forgings in acid service — best corrosion resistance and ductility.31069055180 HB—
AWThis page
As-welded deposit
Weld metal / as-welded joint properties for fabricated vessels; solution anneal after welding where sensitization is a concern.4206803513 HRC1.5 % IACS
Cold drawn
Choose for straight, close-tolerance bar/tube and higher yield strength fasteners and shafts in acid plant hardware.5508003022 HRC1.5 % IACS
Cold worked
Springs, clips and thin strip needing maximum strength; corrosion performance and ductility both reduced versus annealed.7509501530 HRC1.5 % IACS

What is Hastelloy G-AW?

Hastelloy G-AW is Hastelloy G heat treated to AW — weld metal / as-welded joint properties for fabricated vessels; solution anneal after welding where sensitization is a concern. Hastelloy G-AW has a yield strength of 420 MPa (60.9 ksi) and a tensile strength of 680 MPa (98.6 ksi) — stronger than 62% of nickel alloy grades. Elongation at break is 35% and the elastic modulus is 197 GPa (28.6 Msi). Hastelloy G-AW has a density of 8.31 g/cm³ (0.3 lb/in³), heavier than 51% of nickel alloy grades. It melts at 1,260°C (2,300 °F). ANN is the default condition FabDigit quotes; AW is available on request or by drawing note.

Advantages

  • Low embodied carbon — 11 kg CO₂/kg, better than 85% of nickel alloy grades

Limitations

  • Limited service temperature — 500°C (932 °F), worse than 78% of nickel alloy grades

Hastelloy G-AW properties

Typical room-temperature values for Hastelloy G-AW; 23 are specific to this condition. Other listed values are Hastelloy G reference data and may not represent this condition. Bars are the position among nickel alloy grades.

Physical3

Hastelloy G-AW has a density of 8.31 g/cm³ (0.3 lb/in³), heavier than 51% of nickel alloy grades. It melts at 1,260°C (2,300 °F).

Density8.31 g/cm³0.3 lb/in³
Melting Point (Solidus)1,260°C2,300 °F
Liquidus Temperature1,355°C2,471 °F

Mechanical13

Hastelloy G-AW has a yield strength of 420 MPa (60.9 ksi) and a tensile strength of 680 MPa (98.6 ksi) — stronger than 62% of nickel alloy grades. Elongation at break is 35% and the elastic modulus is 197 GPa (28.6 Msi).

Elastic (Young's) Modulus197 GPa28.6 Msi
Shear Modulus76 GPa11 Msi
Bulk Modulus174 GPa25.2 Msi
Poisson's Ratio0.31
Tensile Strength (Ultimate)680 MPa98.6 ksi
Yield Strength (0.2% offset)420 MPa60.9 ksi
Elongation at Break35%
Reduction in Area40%
Shear Strength440 MPa63.8 ksi
Fatigue Strength (Endurance Limit)250 MPa36.3 ksi
Charpy V-Notch Impact (RT)90 J66.4 ft·lbf
Hardness, Brinell200 HB
Hardness, Rockwell B92 HRB

Thermal6

Hastelloy G-AW is rated for continuous service to 500°C (932 °F). It conducts heat at 10.1 W/m·K (5.84 BTU/hr·ft·°F), worse than 84% of nickel alloy grades. Thermal expansion is 13.9 µm/m·K (7.72 µin/in·°F).

Thermal Conductivity10.1 W/m·K5.8 BTU/hr·ft·°F
Specific Heat Capacity445 J/kg·K0.11 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)13.9 µm/m·K7.7 µin/in·°F
Latent Heat of Fusion290 J/g125 BTU/lb
Max Service Temperature (continuous)500°C932 °F
Min Service Temperature-196°C-321 °F

Electrical3

Hastelloy G-AW conducts electricity at 1.5 % IACS, better than 59% of nickel alloy grades.

Electrical Conductivity1.5 % IACS
Electrical Resistivity1.15×10⁻⁶ Ω·m45.3 µΩ·in
Magnetic Responsenon-magnetic

Chemical & Environmental3

Corrosion resistance is very good (78/100), better than 51% of nickel alloy grades.

Galvanic Potential (seawater, vs SCE)-0.15 V
Corrosion ResistanceVery good78/100
Chemical Resistance SummaryExcellent in hot sulfuric acid (all concentrations at moderate temperature), phosphoric acid, mixed acids and sulfuric/chloride contaminated liquors; resists intergranular attack and chloride SCC. Less resistant than C-276 in strongly reducing HCl and than G-30 in hot concentrated phosphoric; avoid wet Cl₂ and high-temperature sensitizing exposures.

Sustainability4

Producing a kilogram of Hastelloy G-AW takes about 145 MJ of energy and emits 11 kg of CO₂ — less than 77% of nickel alloy grades. Typical recycled content is 40%.

Embodied Energy (primary production)145 MJ/kg62,339 BTU/lb
Embodied Carbon (primary production)11 kg CO₂/kg
Embodied Water210 L/kg25.2 gal/lb
Typical Recycled Content40%

Manufacturability7

Hastelloy G-AW's machinability is poor (22/100, better than 64% of nickel alloy grades); weldability very good (70/100); formability fair (40/100).

MachinabilityPoor22/100
Machinability Rating (AISI 1212 = 100 %)12%
WeldabilityVery good70/100
Formability (cold)Fair40/100
Brazeability / SolderabilityFair50/100
PolishabilityVery good70/100
Anodizing Responsen/a — nickel alloy, not anodized; pickle and passivate instead

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

Working with Hastelloy G-AW

Is Hastelloy G easy to machine?

Machine like a gummy austenitic Ni alloy: rigid setups, positive-rake carbide, low speed/heavy feed, flood coolant and no dwelling to avoid work-hardened glaze.

Can Hastelloy G be welded?

GTAW/GMAW/SMAW with matching ERNiCrMo-1 or G-3 filler, stringer beads, low heat input and interpass <100 °C; post-weld solution anneal if the HAZ will see hot acid.

Can Hastelloy G be formed, bent or molded?

Very ductile in the annealed state but work-hardens fast — allow extra press tonnage, generous radii and interstage anneals at ~1100 °C with rapid cooling.

What surface finishes work on Hastelloy G?

Pickle (HNO₃-HF) or bead-blast to remove weld/heat-tint oxide, then passivate; no anodizing — mechanical polish or electropolish for hygienic/acid surfaces.

Hastelloy G 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
C≤ 0.050.03
Mn1 – 21.5
Si≤ 10.5
P≤ 0.04—
S≤ 0.03—
Cr21 – 23.522
Fe18 – 2119.5
Mo5.5 – 7.56.5
Cuimproves resistance in sulfuric acid1.5 – 2.52
Nb+Tastabilizer against intergranular attack1.75 – 2.52.1
Co≤ 2.5—
W≤ 1—
Nibalance, approx. 42–46 %balance—

Hastelloy G-AW — frequently asked

What is Hastelloy G-AW used for?

Hastelloy G-AW is typically used for phosphoric acid production, sulfuric acid handling and chemical process piping. In short: original acid-service Hastelloy; superseded by G-3/G-30; good weldability and formability.

What is the yield strength of Hastelloy G-AW?

Hastelloy G-AW has a typical yield strength of 420 MPa (60.9 ksi) and a tensile strength of 680 MPa (98.6 ksi) — stronger than 62% of nickel alloy grades. Strength varies by condition: see the 5 listed tempers.

Is Hastelloy G-AW easy to machine?

Not especially — machinability is rated poor (22/100, better than 64% of nickel alloy grades). Machine like a gummy austenitic Ni alloy: rigid setups, positive-rake carbide, low speed/heavy feed, flood coolant and no dwelling to avoid work-hardened glaze.

Can Hastelloy G-AW be welded?

Yes — weldability is rated very good (70/100). GTAW/GMAW/SMAW with matching ERNiCrMo-1 or G-3 filler, stringer beads, low heat input and interpass <100 °C; post-weld solution anneal if the HAZ will see hot acid.

What surface finishes work on Hastelloy G-AW?

Pickle (HNO₃-HF) or bead-blast to remove weld/heat-tint oxide, then passivate; no anodizing — mechanical polish or electropolish for hygienic/acid surfaces.

Can Hastelloy G-AW be formed, bent or molded?

Very ductile in the annealed state but work-hardens fast — allow extra press tonnage, generous radii and interstage anneals at ~1100 °C with rapid cooling.

What is the maximum service temperature of Hastelloy G-AW?

Hastelloy G-AW is rated for continuous use to about 500°C (932 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.

What is the difference between Hastelloy G-ANN and Hastelloy G-CW?

ANN is the default condition — standard stocked condition for plate, sheet, tube and forgings in acid service — best corrosion resistance and ductility. CW: springs, clips and thin strip needing maximum strength; corrosion performance and ductility both reduced versus annealed. Yield strength is 310 MPa in ANN versus 750 MPa in CW.

Sources

  1. ASTM B582 — Nickel-Chromium-Iron-Molybdenum-Copper Alloy Plate, Sheet and Strip (N06007) — ASTM International (2019)
  2. ASTM B581 — Ni-Cr-Fe-Mo-Cu Alloy Rod (N06007) — ASTM International (2019)
  3. ASTM B622/B619 — Seamless and Welded Nickel Alloy Pipe and Tube — ASTM International (2020)
  4. Hastelloy alloy G / G-3 technical data — Haynes International (formerly Cabot Corp.) (1990)
  5. ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
  6. ASM Specialty Handbook: Nickel, Cobalt, and Their Alloys — ASM International (2000)

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.