Nickel Alloy 718Plus
UNS N07716 · also Allvac 718Plus
718Plus (UNS N07716, Allvac 718Plus) is a γ′-strengthened derivative of Alloy 718 with cobalt and tungsten additions that raise temperature capability by roughly 55 °C while keeping 718's fabricability and weldability.
Reference datasheet — 718Plus 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
718Plus tempers and conditions
718Plus is supplied in 6 conditions, soft to hard. STA is the default FabDigit quotes; the values on this page are for it.
Compare all 6 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
Solution annealed | Softest supplied condition for machining, cold forming and welding before the customer ages the part. | 500 | 950 | 50 | 22 HRC | — |
As-welded deposit | Condition of the joint before PWHT; useful for fit-up and leak-tight assemblies, but strength must be recovered by a post-weld solution + double age. | 630 | 980 | 25 | 28 HRC | 1.5 % IACS |
Super-solvus solution (1010–1038 °C) + double age | Coarse-grain version for creep- and dwell-crack-growth-limited hot sections; trades some tensile strength and LCF life for creep/rupture capability. | 1,130 | 1,380 | 14 | 42 HRC | — |
AM (L-PBF/EB-PBF) + HIP + solution + double age | Additively manufactured parts after HIP closure of porosity and full aging; slightly lower ductility and more property scatter than wrought forgings. | 1,150 | 1,400 | 14 | 43 HRC | 1.4 % IACS |
STADefault Solution treated and aged | Standard sub-solvus fine-grain heat treatment — the default condition for discs, rings, shafts and fasteners needing maximum tensile/fatigue strength to 704 °C. | 1,220 | 1,480 | 17 | 44 HRC | — |
Direct aged | Retains forging warm-work substructure for the highest yield strength and tensile properties in fasteners and small forgings; lowest ductility of the aged conditions. | 1,290 | 1,520 | 14 | 46 HRC | — |
What is 718Plus?
718Plus (UNS N07716, Allvac 718Plus) is a γ′-strengthened derivative of Alloy 718 with cobalt and tungsten additions that raise temperature capability by roughly 55 °C while keeping 718's fabricability and weldability. It is used for rotating aerospace hardware and is supplied as billet, forgings, bar, sheet and additively built preforms; solution-treated and aged material reaches about 1220 MPa yield, 1480 MPa tensile, 17 % elongation and 44 HRC, with a maximum service temperature of 704 °C. Machinability (12) and formability (10) are poor, so all shaping is done annealed or hot, but weldability at 55 is well above Waspaloy. Alloy 718 remains the cheaper, more widely stocked alternative below 650 °C. 718Plus has a density of 8.22 g/cm³ (0.297 lb/in³), lighter than 60% of nickel alloy grades. It melts at 1,260°C (2,300 °F). 718Plus has a yield strength of 1,220 MPa (177 ksi) and a tensile strength of 1,480 MPa (215 ksi) — stronger than 98% of nickel alloy grades. Elongation at break is 17% and the elastic modulus is 197 GPa (28.6 Msi).
What is 718Plus used for?
- turbine disks
- compressor components
- aerospace rotating hardware
- high-temperature fasteners
Advantages
- High strength — 1,220 MPa (177 ksi), better than 98% of nickel alloy grades
Limitations
- Limited formability — 10/100, worse than 85% of nickel alloy grades
- Limited ductility — 17%, worse than 78% of nickel alloy grades
718Plus properties
Typical room-temperature values for 718Plus-STA; bars are the position among nickel alloy grades.
Physical3
718Plus has a density of 8.22 g/cm³ (0.297 lb/in³), lighter than 60% of nickel alloy grades. It melts at 1,260°C (2,300 °F).
Mechanical16
718Plus has a yield strength of 1,220 MPa (177 ksi) and a tensile strength of 1,480 MPa (215 ksi) — stronger than 98% of nickel alloy grades. Elongation at break is 17% and the elastic modulus is 197 GPa (28.6 Msi).
Thermal6
718Plus is rated for continuous service to 704°C (1,299 °F). It conducts heat at 10.9 W/m·K (6.3 BTU/hr·ft·°F), worse than 64% of nickel alloy grades. Thermal expansion is 12.8 µm/m·K (7.11 µin/in·°F).
Electrical3
718Plus conducts electricity at 1.4 % IACS, worse than 65% of nickel alloy grades.
Chemical & Environmental3
Corrosion resistance is very good (72/100), worse than 71% of nickel alloy grades.
Sustainability4
Producing a kilogram of 718Plus 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%.
Manufacturability8
718Plus's machinability is not recommended (12/100, worse than 86% of nickel alloy grades); weldability good (55/100); formability not recommended (10/100).
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. 718Plus is highlighted; hover a dot for its name, or open the interactive family chart.
Working with 718Plus
Is 718Plus easy to machine?
Machine soft in the annealed condition where possible; when aged use rigid setups, positive-rake carbide or SiAlON ceramic at low speed/high feed with heavy flood coolant, and avoid dwelling to prevent work-hardened glaze.
Can 718Plus be welded?
GTAW/EB/inertia welding with matching 718Plus filler is practical — the γ′ kinetics give better resistance to strain-age (PWHT) cracking than Waspaloy; weld in the annealed condition and follow with full solution + double age.
Can 718Plus be formed, bent or molded?
Hot forge in the ~950–1120 °C window with sub-solvus finishing to control grain size; cold forming only in the annealed state with interstage anneals due to rapid work hardening.
718Plus 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 | 17 – 21 | 18 |
| Cokey addition vs Alloy 718 | 8 – 10 | 9 |
| Fe | 8 – 10 | 9.5 |
| Nbγ′/γ″ former | 5.2 – 5.8 | 5.45 |
| Mo | 2.5 – 3.1 | 2.75 |
| Wsolid-solution strengthener | 0.8 – 1.4 | 1 |
| Alraises Al/Ti ratio → γ′ dominant | 1.2 – 1.7 | 1.45 |
| Ti | 0.5 – 1 | 0.7 |
| C | 0.01 – 0.05 | 0.02 |
| Bgrain-boundary strengthener | 0 – 0.01 | 0.01 |
| Pdeliberate addition, improves creep | 0.01 – 0.02 | 0.01 |
| Mn | ≤ 0.35 | 0.05 |
| Si | ≤ 0.35 | 0.1 |
| S | ≤ 0.02 | 0 |
| Cu | ≤ 0.3 | 0.05 |
| Nibalance, nominally ~52% | balance |
What surface finishes work on 718Plus?
Grit-blast and pickle or electropolish to remove Al/Ti-rich forging scale; not anodizable — use shot peening for fatigue life and aluminide or thermal-spray coatings for hot-gas surfaces.
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 718Plus in FabDigit's catalog. Equivalence is nominal — check the exact specification when certification matters.
- UNS
- N07716
- Trade names
- Allvac 718Plus
How much does 718Plus cost?
718Plus 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.
718Plus — frequently asked
What is 718Plus used for?
718Plus is typically used for turbine disks, compressor components, aerospace rotating hardware and high-temperature fasteners. In short: 55 °C above Alloy 718; weldable disk superalloy; better than Waspaloy fabricability.
What is the yield strength of 718Plus?
718Plus has a typical yield strength of 1,220 MPa (177 ksi) and a tensile strength of 1,480 MPa (215 ksi) — stronger than 98% of nickel alloy grades. Strength varies by condition: see the 6 listed tempers.
Is 718Plus easy to machine?
Not especially — machinability is rated not recommended (12/100, worse than 86% of nickel alloy grades). Machine soft in the annealed condition where possible; when aged use rigid setups, positive-rake carbide or SiAlON ceramic at low speed/high feed with heavy flood coolant, and avoid dwelling to prevent work-hardened glaze.
Can 718Plus be welded?
Yes — weldability is rated good (55/100). GTAW/EB/inertia welding with matching 718Plus filler is practical — the γ′ kinetics give better resistance to strain-age (PWHT) cracking than Waspaloy; weld in the annealed condition and follow with full solution + double age.
What surface finishes work on 718Plus?
Grit-blast and pickle or electropolish to remove Al/Ti-rich forging scale; not anodizable — use shot peening for fatigue life and aluminide or thermal-spray coatings for hot-gas surfaces.
Can 718Plus be formed, bent or molded?
Hot forge in the ~950–1120 °C window with sub-solvus finishing to control grain size; cold forming only in the annealed state with interstage anneals due to rapid work hardening.
What is the maximum service temperature of 718Plus?
718Plus is rated for continuous use to about 704°C (1,299 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between 718Plus-STA and 718Plus-AN?
STA is the default condition — standard sub-solvus fine-grain heat treatment — the default condition for discs, rings, shafts and fasteners needing maximum tensile/fatigue strength to 704 °C. AN: softest supplied condition for machining, cold forming and welding before the customer ages the part. Yield strength is 1,220 MPa in STA versus 500 MPa in AN.
How much does 718Plus cost?
718Plus 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
- ATI Allvac 718Plus Alloy Technical Data Sheet — ATI (Allegheny Technologies) (2020)
- Superalloys 2004 — 'Development of a New 700 °F Capable Nickel Base Superalloy' (Cao & Kennedy) — TMS (2004)
- ASM Handbook Vol. 1 — Properties and Selection: Irons, Steels and High-Performance Alloys — ASM International (1990)
- AMS specifications for 718Plus bar, forgings and rings (nickel alloy, corrosion & heat resistant) — SAE International (2018)
- Superalloy physical/mechanical property compilations (VIM+VAR wrought Ni-Cr-Fe) — MMPDS / Special Metals comparative data (2022)
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.