Nickel Alloy Hastelloy G-3 HF-A
Heat-treated state
UNS N06985 · EN 2.4619
HF-A = hot finished + solution annealed
Choose for heavy plate, forgings and seamless pipe where hot working precedes the final anneal; slightly coarser grain and marginally lower strength.
Values for the HF-A condition
Other Hastelloy G-3 tempers and conditions
Hastelloy G-3 is listed in 5 conditions; see the grade overview at Hastelloy G-3.
Compare all 5 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
HF-AThis page Hot finished + solution annealed | Choose for heavy plate, forgings and seamless pipe where hot working precedes the final anneal; slightly coarser grain and marginally lower strength. | 300 | 670 | 48 | 190 HB | 1.5 % IACS |
SADefault Solution annealed | Standard supply condition for plate, sheet, bar, pipe and fittings; maximum corrosion resistance and ductility. | 310 | 690 | 50 | 185 HB | — |
Cold rolled + annealed sheet/strip | Thin sheet and strip for lining, bellows and formed scrubber components; fine grain gives slightly higher strength with full ductility. | 325 | 700 | 50 | 192 HB | 1.5 % IACS |
As-welded deposit | Property set for all-weld-metal deposits and weld overlay; low carbon keeps HAZ resistant to intergranular attack without post-weld anneal. | 420 | 660 | 35 | 192 HB | 1.5 % IACS |
Cold drawn | Pick when higher strength and tighter tolerance bar/tube are needed for fasteners, shafts or valve trim; corrosion resistance slightly reduced by residual stress. | 720 | 900 | 20 | 27 HRC | 1.5 % IACS |
What is Hastelloy G-3 HF-A?
Hastelloy G-3 HF-A is Hastelloy G-3 heat treated to HF-A — choose for heavy plate, forgings and seamless pipe where hot working precedes the final anneal; slightly coarser grain and marginally lower strength. Hastelloy G-3 HF-A has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 670 MPa (97.2 ksi) — weaker than 78% of nickel alloy grades. Elongation at break is 48% and the elastic modulus is 199 GPa (28.9 Msi). Hastelloy G-3 HF-A 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). SA is the default condition FabDigit quotes; HF-A is available on request or by drawing note.
Advantages
- Ductile — tolerates forming and impact — 48%, better than 83% of nickel alloy grades
- Readily welded — 85/100, better than 83% of nickel alloy grades
- Good corrosion resistance — 88/100, better than 81% of nickel alloy grades
- Forms and bends easily — 74/100, better than 79% of nickel alloy grades
Limitations
- Low strength — 300 MPa (43.5 ksi), worse than 78% of nickel alloy grades
Hastelloy G-3 HF-A properties
Typical room-temperature values for Hastelloy G-3 HF-A; 21 are specific to this condition. Other listed values are Hastelloy G-3 reference data and may not represent this condition. Bars are the position among nickel alloy grades.
Physical3
Hastelloy G-3 HF-A 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).
Mechanical14
Hastelloy G-3 HF-A has a yield strength of 300 MPa (43.5 ksi) and a tensile strength of 670 MPa (97.2 ksi) — weaker than 78% of nickel alloy grades. Elongation at break is 48% and the elastic modulus is 199 GPa (28.9 Msi).
Thermal6
Hastelloy G-3 HF-A is rated for continuous service to 650°C (1,202 °F). It conducts heat at 10.2 W/m·K (5.89 BTU/hr·ft·°F), worse than 79% of nickel alloy grades. Thermal expansion is 13.5 µm/m·K (7.5 µin/in·°F).
Electrical3
Hastelloy G-3 HF-A conducts electricity at 1.5 % IACS, better than 59% of nickel alloy grades.
Chemical & Environmental3
Corrosion resistance is excellent (88/100), better than 81% of nickel alloy grades.
Sustainability4
Producing a kilogram of Hastelloy G-3 HF-A takes about 150 MJ of energy and emits 12 kg of CO₂ — less than 68% of nickel alloy grades. Typical recycled content is 35%.
Manufacturability7
Hastelloy G-3 HF-A's machinability is poor (25/100, better than 76% of nickel alloy grades); weldability excellent (85/100); formability very good (74/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with Hastelloy G-3 HF-A
Is Hastelloy G-3 easy to machine?
Machine like a solid-solution Ni-Cr-Mo alloy: rigid setup, positive-rake sharp carbide, low surface speed (20–35 m/min turning), heavy positive feed to cut under the work-hardened layer, and flood sulfochlorinated coolant.
Can Hastelloy G-3 be welded?
Readily welded by GTAW/GMAW/SMAW with matching ERNiCrMo-9 (AWS A5.14) or ENiCrMo-9 filler; keep interpass below ~150 °C, low heat input and stringer beads; low carbon usually permits use in the as-welded condition.
Can Hastelloy G-3 be formed, bent or molded?
Cold forms well but work-hardens rapidly — allow intermediate solution anneals at 1120–1150 °C with rapid quench; hot work between about 900 and 1180 °C.
What surface finishes work on Hastelloy G-3?
Pickle in nitric-hydrofluoric or grind/blast to remove heat tint and embedded iron before service; electropolishing or mechanical polishing gives the best acid-service surface; no anodizing.
Hastelloy G-3 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 |
|---|---|---|
| Cr | 21 – 23.5 | 22 |
| Fe | 18 – 21 | 19.5 |
| Mo | 6 – 8 | 7 |
| Cu | 1.5 – 2.5 | 2 |
| Co | ≤ 5 | 2 |
| W | ≤ 1.5 | 1 |
| Nb+TaCb+Ta; 8×C minimum stabilization intent | ≤ 0.5 | 0.3 |
| Mn | ≤ 1 | 0.5 |
| Si | ≤ 1 | 0.4 |
| C | ≤ 0.02 | 0.01 |
| P | ≤ 0.04 | — |
| S | ≤ 0.03 | — |
| Nibalance, ~44 % nominal | ≥ 42 (balance) | — |
Hastelloy G-3 HF-A — frequently asked
What is Hastelloy G-3 HF-A used for?
Hastelloy G-3 HF-A is typically used for phosphoric acid production, flue gas desulfurization scrubbers, sulfuric acid coolers and pickling equipment. In short: low-carbon Alloy G upgrade; as-welded acid service; handles phosphoric acid.
What is the yield strength of Hastelloy G-3 HF-A?
Hastelloy G-3 HF-A has a typical yield strength of 300 MPa (43.5 ksi) and a tensile strength of 670 MPa (97.2 ksi) — weaker than 78% of nickel alloy grades. Strength varies by condition: see the 5 listed tempers.
Is Hastelloy G-3 HF-A easy to machine?
Not especially — machinability is rated poor (25/100, better than 76% of nickel alloy grades). Machine like a solid-solution Ni-Cr-Mo alloy: rigid setup, positive-rake sharp carbide, low surface speed (20–35 m/min turning), heavy positive feed to cut under the work-hardened layer, and flood sulfochlorinated coolant.
Can Hastelloy G-3 HF-A be welded?
Yes — weldability is rated excellent (85/100). Readily welded by GTAW/GMAW/SMAW with matching ERNiCrMo-9 (AWS A5.14) or ENiCrMo-9 filler; keep interpass below ~150 °C, low heat input and stringer beads; low carbon usually permits use in the as-welded condition.
What surface finishes work on Hastelloy G-3 HF-A?
Pickle in nitric-hydrofluoric or grind/blast to remove heat tint and embedded iron before service; electropolishing or mechanical polishing gives the best acid-service surface; no anodizing.
Can Hastelloy G-3 HF-A be formed, bent or molded?
Cold forms well but work-hardens rapidly — allow intermediate solution anneals at 1120–1150 °C with rapid quench; hot work between about 900 and 1180 °C.
What is the maximum service temperature of Hastelloy G-3 HF-A?
Hastelloy G-3 HF-A is rated for continuous use to about 650°C (1,202 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between Hastelloy G-3-SA and Hastelloy G-3-CD?
SA is the default condition — standard supply condition for plate, sheet, bar, pipe and fittings; maximum corrosion resistance and ductility. CD: pick when higher strength and tighter tolerance bar/tube are needed for fasteners, shafts or valve trim; corrosion resistance slightly reduced by residual stress. Yield strength is 310 MPa in SA versus 720 MPa in CD.
Sources
- ASTM B582 — Nickel-Chromium-Iron-Molybdenum-Copper Alloy Plate, Sheet, and Strip — ASTM International (2019)
- ASTM B581 — Ni-Cr-Fe-Mo-Cu Alloy Rod, Bar and Wire — ASTM International (2019)
- ASTM B622 / B626 — Seamless and Welded Nickel Alloy Pipe and Tube — ASTM International (2019)
- HASTELLOY G-3 alloy technical data (N06985) — Haynes International (2020)
- ASM Handbook Vol. 2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
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.