Nickel Alloy Hastelloy G-CW (Cold worked)
Supply condition
UNS N06007, N06920 · EN 2.4618
Springs, clips and thin strip needing maximum strength; corrosion performance and ductility both reduced versus annealed.
Values for the CW 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 datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
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. | 300 | 670 | 50 | 175 HB | 1.5 % IACS |
ANNDefault Annealed | Standard stocked condition for plate, sheet, tube and forgings in acid service — best corrosion resistance and ductility. | 310 | 690 | 55 | 180 HB | — |
As-welded deposit | Weld metal / as-welded joint properties for fabricated vessels; solution anneal after welding where sensitization is a concern. | 420 | 680 | 35 | 13 HRC | 1.5 % IACS |
Cold drawn | Choose for straight, close-tolerance bar/tube and higher yield strength fasteners and shafts in acid plant hardware. | 550 | 800 | 30 | 22 HRC | 1.5 % IACS |
CWThis page Cold worked | Springs, clips and thin strip needing maximum strength; corrosion performance and ductility both reduced versus annealed. | 750 | 950 | 15 | 30 HRC | 1.5 % IACS |
What is Hastelloy G-CW?
Hastelloy G-CW is Hastelloy G supplied in the CW condition — springs, clips and thin strip needing maximum strength; corrosion performance and ductility both reduced versus annealed. Hastelloy G-CW has a yield strength of 750 MPa (109 ksi) and a tensile strength of 950 MPa (138 ksi) — stronger than 83% of nickel alloy grades. Elongation at break is 15% and the elastic modulus is 198 GPa (28.7 Msi). Hastelloy G-CW 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; CW is available on request or by drawing note.
Advantages
- Low embodied carbon — 11 kg CO₂/kg, better than 85% of nickel alloy grades
- High strength — 750 MPa (109 ksi), better than 83% of nickel alloy grades
Limitations
- Limited service temperature — 400°C (752 °F), worse than 94% of nickel alloy grades
- Limited ductility — 15%, worse than 81% of nickel alloy grades
Hastelloy G-CW properties
Typical room-temperature values for Hastelloy G-CW; 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-CW 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).
Mechanical13
Hastelloy G-CW has a yield strength of 750 MPa (109 ksi) and a tensile strength of 950 MPa (138 ksi) — stronger than 83% of nickel alloy grades. Elongation at break is 15% and the elastic modulus is 198 GPa (28.7 Msi).
Thermal6
Hastelloy G-CW is rated for continuous service to 400°C (752 °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).
Electrical3
Hastelloy G-CW conducts electricity at 1.5 % IACS, better than 59% of nickel alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (80/100), better than 61% of nickel alloy grades.
Sustainability4
Producing a kilogram of Hastelloy G-CW takes about 145 MJ of energy and emits 11 kg of CO₂ — less than 77% of nickel alloy grades. Typical recycled content is 40%.
Manufacturability7
Hastelloy G-CW's machinability is poor (28/100, better than 82% of nickel alloy grades); weldability good (60/100); formability poor (25/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Hastelloy G-CW
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.
| Element | Spec limit (wt %) | Nominal |
|---|---|---|
| C | ≤ 0.05 | 0.03 |
| Mn | 1 – 2 | 1.5 |
| Si | ≤ 1 | 0.5 |
| P | ≤ 0.04 | — |
| S | ≤ 0.03 | — |
| Cr | 21 – 23.5 | 22 |
| Fe | 18 – 21 | 19.5 |
| Mo | 5.5 – 7.5 | 6.5 |
| Cuimproves resistance in sulfuric acid | 1.5 – 2.5 | 2 |
| Nb+Tastabilizer against intergranular attack | 1.75 – 2.5 | 2.1 |
| Co | ≤ 2.5 | — |
| W | ≤ 1 | — |
| Nibalance, approx. 42–46 % | balance | — |
Hastelloy G-CW — frequently asked
What is Hastelloy G-CW used for?
Hastelloy G-CW 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-CW?
Hastelloy G-CW has a typical yield strength of 750 MPa (109 ksi) and a tensile strength of 950 MPa (138 ksi) — stronger than 83% of nickel alloy grades. Strength varies by condition: see the 5 listed tempers.
Is Hastelloy G-CW easy to machine?
Not especially — machinability is rated poor (28/100, better than 82% 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-CW be welded?
Yes — weldability is rated good (60/100). 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-CW?
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-CW 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-CW?
Hastelloy G-CW is rated for continuous use to about 400°C (752 °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
- ASTM B582 — Nickel-Chromium-Iron-Molybdenum-Copper Alloy Plate, Sheet and Strip (N06007) — ASTM International (2019)
- ASTM B581 — Ni-Cr-Fe-Mo-Cu Alloy Rod (N06007) — ASTM International (2019)
- ASTM B622/B619 — Seamless and Welded Nickel Alloy Pipe and Tube — ASTM International (2020)
- Hastelloy alloy G / G-3 technical data — Haynes International (formerly Cabot Corp.) (1990)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
- 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.