Nickel Alloy Hastelloy G-2
UNS N06975
Hastelloy G-2 (UNS N06975) is a Ni-Cr-Mo-Cu corrosion alloy with improved resistance to mixed nitric/sulfuric acid and to environments that shift between reducing and oxidizing conditions compared with standard Alloy G.
Reference datasheet — Hastelloy G-2 is not in the instant-quote catalog. Upload your part and an engineer will quote it in this grade or suggest the closest stocked equivalent.
Values for the SA condition
Hastelloy G-2 tempers and conditions
Hastelloy G-2 is supplied in 5 conditions, soft to hard. SA is the default FabDigit quotes; the values on this page are for it.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Hot Finished and Annealed | Pick hot finished and annealed heavy plate, forgings and large-diameter bar for pressure-vessel heads and flanges; coarser grain lowers yield to 280 MPa but keeps 50% elongation. | 280 | 635 | 50 | 183 HB | 1.4 % IACS |
SADefault Solution Annealed | Choose mill solution annealed and water quenched sheet, strip, tube or bar for the best corrosion resistance and toughness (295 MPa yield, 48% elongation); the default for chemical equipment. | 295 | 655 | 48 | 190 HB | — |
As-welded deposit | Use to evaluate weld joint properties; as-welded strength approaches the annealed base metal, but weld dendritic segregation lowers the corrosion margin, so solution treat after welding for severe service. | 340 | 640 | 35 | 200 HB | 1.4 % IACS |
Cold drawn | Choose for fasteners, valve stems and pump shafts needing 550 MPa yield with tight dimensional accuracy; control the cold-drawing residual stress with a stress-relief treatment. | 550 | 790 | 28 | 22 HRC | 1.4 % IACS |
Cold Worked / Hard strip and tube | Pick for spring elements and thin-wall high-pressure tubing needing 720 MPa yield; ductility falls to 12% and intergranular corrosion margin drops, so solution treat after forming. | 720 | 930 | 12 | 28 HRC | 1.4 % IACS |
What is Hastelloy G-2?
Hastelloy G-2 (UNS N06975) is a Ni-Cr-Mo-Cu corrosion alloy with improved resistance to mixed nitric/sulfuric acid and to environments that shift between reducing and oxidizing conditions compared with standard Alloy G. It is used for acid-plant equipment in SA, HFA, CD, CW-H and AW conditions, as plate, sheet, tube and bar. Annealed properties are 295 MPa yield, 655 MPa tensile, 48% elongation and 190 HB (90 HRB), with a maximum service temperature of 540 °C and a corrosion-resistance score of 82. Machinability is low (score 20) and the grade is largely superseded by G-3 and G-30. Hastelloy G-2 has a density of 8.14 g/cm³ (0.294 lb/in³), lighter than 74% of nickel alloy grades. It melts at 1,330°C (2,426 °F). Hastelloy G-2 has a yield strength of 295 MPa (42.8 ksi) and a tensile strength of 655 MPa (95 ksi) — weaker than 80% of nickel alloy grades. Elongation at break is 48% and the elastic modulus is 199 GPa (28.9 Msi).
What is Hastelloy G-2 used for?
- sulfuric acid alkylation units
- mixed acid service
- chemical process vessels
- acid coolers
Advantages
- Ductile — tolerates forming and impact — 48%, better than 83% of nickel alloy grades
Limitations
- Low strength — 295 MPa (42.8 ksi), worse than 80% of nickel alloy grades
- Limited service temperature — 540°C (1,004 °F), worse than 75% of nickel alloy grades
Hastelloy G-2 properties
Typical room-temperature values for Hastelloy G-2-SA; bars are the position among nickel alloy grades.
Physical3
Hastelloy G-2 has a density of 8.14 g/cm³ (0.294 lb/in³), lighter than 74% of nickel alloy grades. It melts at 1,330°C (2,426 °F).
Mechanical13
Hastelloy G-2 has a yield strength of 295 MPa (42.8 ksi) and a tensile strength of 655 MPa (95 ksi) — weaker than 80% of nickel alloy grades. Elongation at break is 48% and the elastic modulus is 199 GPa (28.9 Msi).
Thermal6
Hastelloy G-2 is rated for continuous service to 540°C (1,004 °F). It conducts heat at 10.5 W/m·K (6.07 BTU/hr·ft·°F), worse than 73% of nickel alloy grades. Thermal expansion is 13.6 µm/m·K (7.56 µin/in·°F).
Electrical3
Hastelloy G-2 conducts electricity at 1.4 % IACS, worse than 65% of nickel alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (82/100), better than 67% of nickel alloy grades.
Sustainability4
Producing a kilogram of Hastelloy G-2 takes about 150 MJ of energy and emits 12 kg of CO₂ — less than 68% of nickel alloy grades. Typical recycled content is 35%.
Manufacturability8
Hastelloy G-2's machinability is poor (20/100, better than 53% of nickel alloy grades); weldability very good (72/100); formability good (65/100).
Common Calculations5
Values are nominal handbook figures for design screening. Certified mill or lot data ships with every FabDigit order on request.
Strength versus weight in the nickel alloy family
Yield strength against density for every nickel alloy grade FabDigit runs. Hastelloy G-2 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with Hastelloy G-2
Is Hastelloy G-2 easy to machine?
Handle as a nickel corrosion alloy: low speed with heavy feed, rigid clamping, sharp positive-rake tooling (K/M-grade carbide) and generous emulsion coolant to prevent rubbing that builds a work-hardened layer.
Can Hastelloy G-2 be welded?
Mainly GTAW and GMAW using matching filler or ERNiCrMo-1 (Alloy G-3). Keep heat input low and interpass temperature below 100 °C, no preheat required; a post-weld solution treatment can be used for severe corrosion service.
Can Hastelloy G-2 be formed, bent or molded?
Ductile in the annealed condition for cold pressing, plate rolling and tube expanding, but the work-hardening rate is high, so deep forming needs intermediate anneals at about 1120 °C followed by water quench. Hot work at roughly 900–1180 °C.
Hastelloy G-2 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 |
|---|---|---|
| Ni | 47 – 52 | 49.5 |
| Cr | 23 – 26 | 24.5 |
| Mo | 5 – 7 | 6 |
| Cuimproves corrosion resistance in reducing acids | 0.7 – 1.2 | 0.9 |
| Tistabilizer, suppresses intergranular corrosion | 0.7 – 1.5 | 1 |
| C | ≤ 0.03 | 0.02 |
| Mn | ≤ 1 | 0.5 |
| Si | ≤ 1 | 0.4 |
| P | ≤ 0.03 | |
| S | ≤ 0.03 | |
| Febalance, typically 15–20% | balance |
What surface finishes work on Hastelloy G-2?
Not suitable for anodizing. Remove scale by nitric-hydrofluoric pickling and then passivate, or mechanically polish / electropolish to a low roughness to improve pitting resistance.
Surface treatments FabDigit runs on nickel alloy parts — pick them in the quote configurator or call them out on the drawing. Each links to its datasheet in the surface-finish library (thickness, specs, call-out, material verdicts).
Plating
Thermal Spray
Equivalent designations
Standards and trade names that resolve to Nickel Alloy Hastelloy G-2 in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- N06975
How much does Hastelloy G-2 cost?
Hastelloy G-2 is a high-cost nickel alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Hastelloy G-2 — frequently asked
What is Hastelloy G-2 used for?
Hastelloy G-2 is typically used for sulfuric acid alkylation units, mixed acid service, chemical process vessels and acid coolers. In short: mixed nitric-sulfuric acid grade; cu-bearing Ni-Cr-Mo alloy; 540 °C service limit.
What is the yield strength of Hastelloy G-2?
Hastelloy G-2 has a typical yield strength of 295 MPa (42.8 ksi) and a tensile strength of 655 MPa (95 ksi) — weaker than 80% of nickel alloy grades. Strength varies by condition: see the 5 listed tempers.
Is Hastelloy G-2 easy to machine?
Not especially — machinability is rated poor (20/100, better than 53% of nickel alloy grades). Handle as a nickel corrosion alloy: low speed with heavy feed, rigid clamping, sharp positive-rake tooling (K/M-grade carbide) and generous emulsion coolant to prevent rubbing that builds a work-hardened layer.
Can Hastelloy G-2 be welded?
Yes — weldability is rated very good (72/100). Mainly GTAW and GMAW using matching filler or ERNiCrMo-1 (Alloy G-3). Keep heat input low and interpass temperature below 100 °C, no preheat required; a post-weld solution treatment can be used for severe corrosion service.
What surface finishes work on Hastelloy G-2?
Not suitable for anodizing. Remove scale by nitric-hydrofluoric pickling and then passivate, or mechanically polish / electropolish to a low roughness to improve pitting resistance.
Can Hastelloy G-2 be formed, bent or molded?
Ductile in the annealed condition for cold pressing, plate rolling and tube expanding, but the work-hardening rate is high, so deep forming needs intermediate anneals at about 1120 °C followed by water quench. Hot work at roughly 900–1180 °C.
What is the maximum service temperature of Hastelloy G-2?
Hastelloy G-2 is rated for continuous use to about 540°C (1,004 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Hastelloy G-2-SA and Hastelloy G-2 CW-H?
SA is the default condition — choose mill solution annealed and water quenched sheet, strip, tube or bar for the best corrosion resistance and toughness (295 MPa yield, 48% elongation); the default for chemical equipment. CW-H: pick for spring elements and thin-wall high-pressure tubing needing 720 MPa yield; ductility falls to 12% and intergranular corrosion margin drops, so solution treat after forming. Yield strength is 295 MPa in SA versus 720 MPa in CW-H.
How much does Hastelloy G-2 cost?
Hastelloy G-2 is a high-cost nickel alloy ($$$$), pricier than about 78% of the materials FabDigit quotes. Part price depends far more on geometry, tolerance and quantity than on the raw stock — upload a CAD file for a live quote.
Sources
- ASTM B582 — Ni-Cr-Fe-Mo-Cu Alloy Plate, Sheet and Strip (N06975) — ASTM International (2019)
- ASTM B581 — Ni-Cr-Fe-Mo-Cu Alloy Rod and Bar (N06975) — ASTM International (2019)
- ASTM B622 / B626 — Seamless and Welded Ni-Alloy Pipe and Tube — ASTM International (2022)
- HASTELLOY G-series Alloys (G, G-2, G-3, G-30) technical data — Haynes International (2020)
- ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
- ASM Handbook Vol.13B — Corrosion: Materials — ASM International (2005)
Property data is compiled from published supplier and standards handbooks and normalised for comparison; hardness values on non-Brinell scales are converted approximately for charting only. Manufacturability limits are FabDigit quote-engine defaults and may be relaxed by engineering review. Nothing on this page is a certification — request mill certs, CoC or material test reports with your order.