Nickel Alloy N09777
UNS N09777
A precipitation-hardenable, controlled-expansion nickel-iron superalloy used where dimensional stability and thermal expansion matching are needed alongside elevated-temperature strength, such as in gas turbine casings and seals.
Reference datasheet — N09777 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 STA condition
N09777 tempers and conditions
N09777 is supplied in 4 conditions, soft to hard. STA is the default FabDigit quotes; the values on this page are for it.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed | Softest condition — choose for machining, cold forming, welding or forging stock before final ageing. | 480 | 830 | 35 | 200 HB | — |
Cold drawn | Cold-worked bar, wire or strip supplied for close tolerance and finish; age after machining to develop final properties. | 830 | 1,030 | 15 | 32 HRC | 1.7 % IACS |
STADefault Solution treated and aged | Standard delivered/engineering condition — full γ″/η precipitation strength with low, linear expansion for turbine casings, seals and rings. | 1,000 | 1,275 | 15 | 40 HRC | — |
Direct aged | Pick when the finer as-forged grain size is wanted for higher yield strength and fatigue life at some loss of ductility. | 1,100 | 1,380 | 12 | 43 HRC | — |
What is N09777?
A precipitation-hardenable, controlled-expansion nickel-iron superalloy used where dimensional stability and thermal expansion matching are needed alongside elevated-temperature strength, such as in gas turbine casings and seals. N09777 has a density of 8.14 g/cm³ (0.294 lb/in³), lighter than 74% of nickel alloy grades. It melts at 1,345°C (2,453 °F). N09777 has a yield strength of 1,000 MPa (145 ksi) and a tensile strength of 1,275 MPa (185 ksi) — stronger than 95% of nickel alloy grades. Elongation at break is 15% and the elastic modulus is 160 GPa (23.2 Msi).
What is N09777 used for?
- gas turbine casings
- seal rings
- aerospace low-expansion structural parts
Advantages
- High strength — 1,000 MPa (145 ksi), better than 95% of nickel alloy grades
- High electrical conductivity — 1.8 % IACS, better than 82% of nickel alloy grades
Limitations
- High embodied carbon — 17 kg CO₂/kg, worse than 96% of nickel alloy grades
- Needs corrosion protection — 40/100, worse than 95% of nickel alloy grades
- Low stiffness — 160 GPa (23.2 Msi), worse than 92% of nickel alloy grades
- Low fracture toughness — 70 MPa·√m (63.7 ksi·√in), worse than 85% of nickel alloy grades
- Limited ductility — 15%, worse than 81% of nickel alloy grades
N09777 properties
Typical room-temperature values for N09777-STA; bars are the position among nickel alloy grades.
Physical3
N09777 has a density of 8.14 g/cm³ (0.294 lb/in³), lighter than 74% of nickel alloy grades. It melts at 1,345°C (2,453 °F).
Mechanical14
N09777 has a yield strength of 1,000 MPa (145 ksi) and a tensile strength of 1,275 MPa (185 ksi) — stronger than 95% of nickel alloy grades. Elongation at break is 15% and the elastic modulus is 160 GPa (23.2 Msi).
Thermal6
N09777 is rated for continuous service to 650°C (1,202 °F). It conducts heat at 13 W/m·K (7.51 BTU/hr·ft·°F), better than 71% of nickel alloy grades. Thermal expansion is 7.4 µm/m·K (4.11 µin/in·°F).
Electrical3
N09777 conducts electricity at 1.8 % IACS, better than 82% of nickel alloy grades.
Chemical & Environmental3
Corrosion resistance is fair (40/100), worse than 95% of nickel alloy grades.
Sustainability4
Producing a kilogram of N09777 takes about 230 MJ of energy and emits 17 kg of CO₂ — more than 91% of nickel alloy grades. Typical recycled content is 25%.
Manufacturability7
N09777's machinability is poor (22/100, better than 64% of nickel alloy grades); weldability fair (45/100); formability poor (20/100).
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. N09777 is highlighted; hover a dot for its name, or open the interactive family chart.
Working with N09777
Is N09777 easy to machine?
Machine in the solution-annealed state where possible; rigid setups, positive-rake carbide or ceramic tools, low surface speed (~15–25 m/min carbide in aged material), heavy feed and flood coolant to avoid work hardening and glazing.
Can N09777 be welded?
GTAW/EBW in the solution-annealed condition with matched or Nb-bearing filler; keep heat input low, avoid restraint, and re-solution + double age after welding to restore strength and expansion behaviour.
Can N09777 be formed, bent or molded?
Hot work 900–1120 °C with finishing below 1010 °C for fine grain; cold forming only from the annealed condition with intermediate anneals — aged material is essentially non-formable.
N09777 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 | 24 – 26 | 25 |
| Co | 28 – 31 | 29 |
| Cradded for oxidation / SAGBO resistance | 5 – 6 | 5.5 |
| Nbprincipal γ″ former (Nb+Ta) | 4.4 – 5.2 | 4.8 |
| Ti | 0.6 – 1 | 0.85 |
| Al | 0.3 – 0.7 | 0.5 |
| Si | 0.15 – 0.5 | 0.35 |
| C | ≤ 0.05 | 0.03 |
| Mn | ≤ 0.5 | |
| B | ≤ 0.01 | 0.01 |
| P | ≤ 0.02 | |
| S | ≤ 0.02 | |
| Febalance, approx. 32–36 % | balance |
What surface finishes work on N09777?
Not anodizable; grind/polish with the low thermal conductivity in mind, and use aluminide, thermal-barrier or plated coatings where wet-corrosion or long-term oxidation protection is required.
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
How much does N09777 cost?
N09777 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.
N09777 — frequently asked
What is N09777 used for?
N09777 is typically used for gas turbine casings, seal rings and aerospace low-expansion structural parts. In short: low expansion, high strength; aged to 40 HRC; needs coatings for corrosion.
What is the yield strength of N09777?
N09777 has a typical yield strength of 1,000 MPa (145 ksi) and a tensile strength of 1,275 MPa (185 ksi) — stronger than 95% of nickel alloy grades. Strength varies by condition: see the 4 listed tempers.
Is N09777 easy to machine?
Not especially — machinability is rated poor (22/100, better than 64% of nickel alloy grades). Machine in the solution-annealed state where possible; rigid setups, positive-rake carbide or ceramic tools, low surface speed (~15–25 m/min carbide in aged material), heavy feed and flood coolant to avoid work hardening and glazing.
Can N09777 be welded?
With care — weldability is rated fair (45/100). GTAW/EBW in the solution-annealed condition with matched or Nb-bearing filler; keep heat input low, avoid restraint, and re-solution + double age after welding to restore strength and expansion behaviour.
What surface finishes work on N09777?
Not anodizable; grind/polish with the low thermal conductivity in mind, and use aluminide, thermal-barrier or plated coatings where wet-corrosion or long-term oxidation protection is required.
Can N09777 be formed, bent or molded?
Hot work 900–1120 °C with finishing below 1010 °C for fine grain; cold forming only from the annealed condition with intermediate anneals — aged material is essentially non-formable.
What is the maximum service temperature of N09777?
N09777 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 N09777-STA and N09777-SA?
STA is the default condition — standard delivered/engineering condition — full γ″/η precipitation strength with low, linear expansion for turbine casings, seals and rings. SA: softest condition — choose for machining, cold forming, welding or forging stock before final ageing. Yield strength is 1,000 MPa in STA versus 480 MPa in SA.
How much does N09777 cost?
N09777 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
- Controlled-expansion Fe-Ni-Co-Cr superalloy (Thermo-Span type) technical datasheet — Carpenter Technology (2020)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels, and High-Performance Alloys (low-expansion superalloys) — ASM International (1990)
- ASM Specialty Handbook: Heat-Resistant Materials — ASM International (1997)
- Metals & Alloys in the Unified Numbering System (UNS N09777) — SAE/ASTM (2017)
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.