Nickel Alloy N07776 HF+A
Heat-treated state
UNS N07776
HF+A = hot finished / hot worked and directly aged
Pick for large forged or hot-rolled sections where a full solution treat is impractical; slightly lower and more scattered properties than STA.
Values for the HF+A condition
Other N07776 tempers and conditions
N07776 is listed in 6 conditions; see the grade overview at N07776.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed | Pick for forming, machining of complex shapes and welding before final ageing. | 420 | 850 | 48 | 200 HB | — |
CW+A 120 ksi | Lowest strength level of the oil-country / sour-service bar grades, chosen when maximum toughness and SSC margin are wanted. | 880 | 1,170 | 25 | 32 HRC | 1.4 % IACS |
HF+AThis page Hot finished / hot worked and directly aged | Pick for large forged or hot-rolled sections where a full solution treat is impractical; slightly lower and more scattered properties than STA. | 965 | 1,240 | 20 | 35 HRC | 1.4 % IACS |
STADefault Solution treated and aged | Standard delivered condition for high-strength turbine, fastener and downhole components. | 1,010 | 1,300 | 22 | 36 HRC | — |
CW+A 140 ksi | Common downhole/completion bar strength level balancing strength and environmental cracking resistance. | 1,015 | 1,240 | 20 | 36 HRC | 1.4 % IACS |
CW+A 150 ksi | Highest standard strength level for heavily loaded fasteners and tools; least ductility and tightest hardness cap for sour service. | 1,090 | 1,320 | 17 | 39 HRC | 1.4 % IACS |
What is N07776 HF+A?
N07776 HF+A is N07776 heat treated to HF+A — pick for large forged or hot-rolled sections where a full solution treat is impractical; slightly lower and more scattered properties than STA. N07776 HF+A has a yield strength of 965 MPa (140 ksi) and a tensile strength of 1,240 MPa (180 ksi) — stronger than 95% of nickel alloy grades. Elongation at break is 20% and the elastic modulus is 204 GPa (29.6 Msi). N07776 HF+A has a density of 8.3 g/cm³ (0.3 lb/in³), lighter than 52% of nickel alloy grades. It melts at 1,265°C (2,309 °F). STA is the default condition FabDigit quotes; HF+A is available on request or by drawing note.
Advantages
- High strength — 965 MPa (140 ksi), better than 95% of nickel alloy grades
Limitations
- Limited ductility — 20%, worse than 76% of nickel alloy grades
- Difficult to weld — 38/100, worse than 75% of nickel alloy grades
N07776 HF+A properties
Typical room-temperature values for N07776 HF+A; 22 are specific to this condition. Other listed values are N07776 reference data and may not represent this condition. Bars are the position among nickel alloy grades.
Physical3
N07776 HF+A has a density of 8.3 g/cm³ (0.3 lb/in³), lighter than 52% of nickel alloy grades. It melts at 1,265°C (2,309 °F).
Mechanical15
N07776 HF+A has a yield strength of 965 MPa (140 ksi) and a tensile strength of 1,240 MPa (180 ksi) — stronger than 95% of nickel alloy grades. Elongation at break is 20% and the elastic modulus is 204 GPa (29.6 Msi).
Thermal6
N07776 HF+A is rated for continuous service to 650°C (1,202 °F). It conducts heat at 10.8 W/m·K (6.24 BTU/hr·ft·°F), worse than 66% of nickel alloy grades. Thermal expansion is 12.8 µm/m·K (7.11 µin/in·°F).
Electrical3
N07776 HF+A conducts electricity at 1.4 % IACS, worse than 65% of nickel alloy grades.
Chemical & Environmental3
Corrosion resistance is excellent (86/100), better than 77% of nickel alloy grades.
Sustainability4
Producing a kilogram of N07776 HF+A takes about 215 MJ of energy and emits 14.5 kg of CO₂ — more than 84% of nickel alloy grades. Typical recycled content is 35%.
Manufacturability7
N07776 HF+A's machinability is poor (15/100, worse than 76% of nickel alloy grades); weldability fair (38/100); formability poor (22/100).
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with N07776 HF+A
Is N07776 easy to machine?
Machine in the solution-annealed state where possible; use rigid setups, positive-rake carbide or ceramic tools, low speed/heavy feed, flood high-pressure coolant, and avoid dwelling to prevent severe work hardening.
Can N07776 be welded?
GTAW/EBW in the solution-annealed condition with matching or Ni-Cr-Mo filler, low heat input and interpass control, then re-solution and age; welding fully aged material risks strain-age and HAZ liquation cracking.
Can N07776 be formed, bent or molded?
Hot work in the ~1000–1150 °C range with adequate finishing strain; cold forming only in the annealed temper with high tooling loads, generous radii and interstage anneals.
What surface finishes work on N07776?
Not anodizable — pickle/passivate or electropolish for corrosion service; shot peening improves fatigue and SCC life, and electroless Ni or PVD coatings can be used for galling control.
N07776 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 |
|---|---|---|
| Niapproximate for this Ni-Cr-Fe PH class; confirm against order spec | 50 – 60 | 56 |
| Crprovides passivity / pitting resistance | 19 – 23 | 21 |
| Mosolid-solution strengthener, crevice/pitting resistance | 7 – 9.5 | 8 |
| Nbγ″ former | 2.5 – 4.5 | 3.4 |
| Tiγ′ former | 1 – 1.7 | 1.4 |
| Al | 0 – 0.7 | 0.3 |
| C | ≤ 0.03 | 0.02 |
| Mn | ≤ 0.35 | — |
| Si | ≤ 0.2 | — |
| S | ≤ 0.01 | — |
| P | ≤ 0.02 | — |
| Cu | ≤ 0.5 | — |
| Febalance, typically 6–12 % | balance | — |
N07776 HF+A — frequently asked
What is N07776 HF+A used for?
N07776 HF+A is typically used for turbine discs, aerospace structural parts and high-temperature fasteners. In short: aged strength to 1300 MPa; hot strength to 650 °C; hard to machine, weld annealed.
What is the yield strength of N07776 HF+A?
N07776 HF+A has a typical yield strength of 965 MPa (140 ksi) and a tensile strength of 1,240 MPa (180 ksi) — stronger than 95% of nickel alloy grades. Strength varies by condition: see the 6 listed tempers.
Is N07776 HF+A easy to machine?
Not especially — machinability is rated poor (15/100, worse than 76% of nickel alloy grades). Machine in the solution-annealed state where possible; use rigid setups, positive-rake carbide or ceramic tools, low speed/heavy feed, flood high-pressure coolant, and avoid dwelling to prevent severe work hardening.
Can N07776 HF+A be welded?
With care — weldability is rated fair (38/100). GTAW/EBW in the solution-annealed condition with matching or Ni-Cr-Mo filler, low heat input and interpass control, then re-solution and age; welding fully aged material risks strain-age and HAZ liquation cracking.
What surface finishes work on N07776 HF+A?
Not anodizable — pickle/passivate or electropolish for corrosion service; shot peening improves fatigue and SCC life, and electroless Ni or PVD coatings can be used for galling control.
Can N07776 HF+A be formed, bent or molded?
Hot work in the ~1000–1150 °C range with adequate finishing strain; cold forming only in the annealed temper with high tooling loads, generous radii and interstage anneals.
What is the maximum service temperature of N07776 HF+A?
N07776 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 N07776-STA and N07776-SA?
STA is the default condition — standard delivered condition for high-strength turbine, fastener and downhole components. SA: pick for forming, machining of complex shapes and welding before final ageing. Yield strength is 1,010 MPa in STA versus 420 MPa in SA.
Sources
- ASTM B637 — Precipitation-Hardening Nickel Alloy Bars, Forgings and Forging Stock for High-Temperature Service — ASTM International (2018)
- ASTM B805 / API 6ACRA — age-hardened corrosion-resistant nickel alloy bar for oil and gas service — ASTM International / API (2020)
- SAE/ASTM DS-56 Metals & Alloys in the Unified Numbering System (UNS) — SAE International (2019)
- ASM Handbook Vol.1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- Age-hardenable Ni-Cr-Mo alloy bar datasheets (INCONEL 725/718 class) — Special Metals / VDM Metals (2022)
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.