FabDigitFabDigit

Nickel Alloy Inconel 718 Stress Relieved

Heat-treated state

UNS N07718 · EN 2.4668 · GB GH4169

Used to remove residual stress from cold work, welding or laser powder-bed builds before machining/aging.

Values for the Stress Relieved condition

Other Inconel 718 tempers and conditions

Inconel 718 is listed in 11 conditions; see the grade overview at Inconel 718.

Compare all 11 conditionsHide
Condition · open for datasheetBest forYield MPaTensile MPaElong. %HardnessConductivity
1010–1065 °C mill anneal (soft, tube/sheet condition, AMS 5589/5590)
Softest wrought condition, chosen for tube bending, deep drawing and welded fabrication.46090050180 HB1.4 % IACS
954–1010 °C solution treated, quenched (pre-age condition, AMS 5596/5662 base)
Standard stocked condition for forming, machining and welding before customer-performed aging.55096545200 HB—
As-Fabricated
Mill/as-fabricated UNS N07718 supplied without final solution + precipitation treatment; moderate strength, high ductility, readily formed and welded before aging.5609653825 HRC1.4 % IACS
Hot isostatic pressed
Pick for cast or additively built 718 that must be pore-free and fatigue-critical; normally followed by aging.6201,0303815 HRC1.4 % IACS
as-built laser powder-bed fusion / DMLS (no heat treatment)
Reference state for AM prints straight off the plate; anisotropic with high residual stress, normally stress relieved + HIP + aged before service.7001,0102730 HRC11 W/m·K
as-hot-worked bar and plate
Lowest-cost mill condition for re-forging or for parts that will be solution treated and aged later.7001,0503025 HRC1.4 % IACS
Stress RelievedThis page
870–1065 °C stress relief (cold-worked wrought or as-built AM parts)
Used to remove residual stress from cold work, welding or laser powder-bed builds before machining/aging.7401,0303032 HRC1.4 % IACS
investment cast 718 per AMS 5383
For complex cast housings, casings and manifolds where wrought properties are not required.800965836 HRC1.4 % IACS
cold drawn / cold rolled bar, wire and strip (unaged)
Chosen for close tolerance bar, springs and wire where cold-work strength and good surface are needed.1,0501,2501238 HRC1.4 % IACS
Solution treated + precipitation aged
Full-strength service condition for turbine discs, shafts, fasteners and downhole tooling to 650 °C.1,1701,3752042 HRC11 W/m·K
hot/cold worked then aged without re-solution
Fine-grain, highest-strength route for discs and fasteners where creep at ≤650 °C and tensile strength dominate.1,2501,4501545 HRC1.4 % IACS

What is Inconel 718 Stress Relieved?

Inconel 718 Stress Relieved is Inconel 718 heat treated to Stress Relieved — used to remove residual stress from cold work, welding or laser powder-bed builds before machining/aging. Inconel 718 Stress Relieved has a yield strength of 740 MPa (107 ksi) and a tensile strength of 1,030 MPa (149 ksi) — stronger than 82% of nickel alloy grades. Elongation at break is 30% and the elastic modulus is 200 GPa (29 Msi). Inconel 718 Stress Relieved has a density of 8.19 g/cm³ (0.296 lb/in³), lighter than 68% of nickel alloy grades. It melts at 1,260°C (2,300 °F). Solution Annealed is the default condition FabDigit quotes; Stress Relieved is available on request or by drawing note.

Advantages

  • Polishes to a fine finish — 80/100, better than 97% of nickel alloy grades
  • High strength — 740 MPa (107 ksi), better than 82% of nickel alloy grades
  • Tough — resists crack growth — 120 MPa·√m (109.2 ksi·√in), better than 75% of nickel alloy grades

Limitations

  • High embodied carbon — 16 kg CO₂/kg, worse than 93% of nickel alloy grades

Inconel 718 Stress Relieved properties

Typical room-temperature values for Inconel 718 Stress Relieved; 22 are specific to this condition. Other listed values are Inconel 718 reference data and may not represent this condition. Bars are the position among nickel alloy grades.

Physical3

Inconel 718 Stress Relieved has a density of 8.19 g/cm³ (0.296 lb/in³), lighter than 68% of nickel alloy grades. It melts at 1,260°C (2,300 °F).

Density8.19 g/cm³0.3 lb/in³
Melting Point (Solidus)1,260°C2,300 °F
Liquidus Temperature1,336°C2,437 °F

Mechanical15

Inconel 718 Stress Relieved has a yield strength of 740 MPa (107 ksi) and a tensile strength of 1,030 MPa (149 ksi) — stronger than 82% of nickel alloy grades. Elongation at break is 30% and the elastic modulus is 200 GPa (29 Msi).

Elastic (Young's) Modulus200 GPa29 Msi
Shear Modulus78 GPa11.3 Msi
Bulk Modulus163 GPa23.6 Msi
Poisson's Ratio0.29
Tensile Strength (Ultimate)1,030 MPa149 ksi
Yield Strength (0.2% offset)740 MPa107 ksi
Elongation at Break30%
Reduction in Area45%
Shear Strength650 MPa94.3 ksi
Fatigue Strength (Endurance Limit)440 MPa63.8 ksi
Fracture Toughness (K_IC)120 MPa·√m109 ksi·√in
Charpy V-Notch Impact (RT)70 J51.6 ft·lbf
Hardness, Brinell300 HB
Hardness, Rockwell B92 HRB
Hardness, Vickers318 HV

Thermal6

Inconel 718 Stress Relieved is rated for continuous service to 650°C (1,202 °F). It conducts heat at 11.4 W/m·K (6.59 BTU/hr·ft·°F), better than 53% of nickel alloy grades. Thermal expansion is 13 µm/m·K (7.22 µin/in·°F).

Thermal Conductivity11.4 W/m·K6.6 BTU/hr·ft·°F
Specific Heat Capacity435 J/kg·K0.1 BTU/lb·°F
Thermal Expansion (CTE, 20–100 °C)13 µm/m·K7.2 µin/in·°F
Latent Heat of Fusion210 J/g90.3 BTU/lb
Max Service Temperature (continuous)650°C1,202 °F
Min Service Temperature-253°C-423 °F

Electrical3

Inconel 718 Stress Relieved conducts electricity at 1.4 % IACS, worse than 65% of nickel alloy grades.

Electrical Conductivity1.4 % IACS
Electrical Resistivity1.25×10⁻⁶ Ω·m49.2 µΩ·in
Magnetic Responsenon-magnetic (relative permeability ≈1.001 at RT; Curie point ≈ −112 °C)

Chemical & Environmental3

Corrosion resistance is very good (78/100), better than 51% of nickel alloy grades.

Galvanic Potential (seawater, vs SCE)-0.1 V
Corrosion ResistanceVery good78/100
Chemical Resistance SummaryExcellent in oxidizing/steam/seawater and in sour (H₂S/CO₂) oil-and-gas service per NACE MR0175 limits; good resistance to dilute acids and chlorides, better pitting resistance than 300-series stainless; attacked by hot concentrated HCl/H₂SO₄ and by molten sulphur-bearing salts; usable in air up to ~980 °C for oxidation but strength limits use to ~650 °C.

Sustainability4

Producing a kilogram of Inconel 718 Stress Relieved takes about 250 MJ of energy and emits 16 kg of CO₂ — more than 97% of nickel alloy grades. Typical recycled content is 35%.

Embodied Energy (primary production)250 MJ/kg107,481 BTU/lb
Embodied Carbon (primary production)16 kg CO₂/kg
Embodied Water250 L/kg30 gal/lb
Typical Recycled Content35%

Manufacturability8

Inconel 718 Stress Relieved's machinability is poor (16/100, worse than 71% of nickel alloy grades); weldability good (65/100); formability fair (40/100).

MachinabilityPoor16/100
Machinability Rating (AISI 1212 = 100 %)13%
WeldabilityGood65/100
Formability (cold)Fair40/100
CastabilityFair45/100
Brazeability / SolderabilityGood55/100
PolishabilityVery good80/100
Anodizing Responsen/a — not anodizable; surfaces are typically passivated, electropolished, shot-peened or coated (Al/Cr diffusion, PVD).

Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.

Working with Inconel 718 Stress Relieved

Is Inconel 718 easy to machine?

Machine in the solution-annealed state where possible; rigid setups, low speed (20–35 m/min carbide, 150–250 m/min ceramic), heavy positive feed, sharp tools and flood coolant to beat work hardening and notch wear.

Can Inconel 718 be welded?

Very good fusion weldability by GTAW/EBW/LBW with ERNiFeCr-2 (718) filler in the annealed condition; keep heat input low, avoid restrained thick sections, and post-weld solution treat + age to restore full strength.

Can Inconel 718 be formed, bent or molded?

Hot work at 1010–1120 °C; cold form only from annealed stock with high tooling forces and intermediate anneals — springback and tool wear are severe.

What surface finishes work on Inconel 718?

Not anodizable; use pickling/passivation, electropolishing, abrasive blasting or shot peening for fatigue, plus diffusion or PVD coatings for high-temperature wear.

Inconel 718 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.

ElementSpec limit (wt %)Nominal
Niplus Co if reported50 – 5553
Cr17 – 2119
NbNb + Ta4.75 – 5.55.13
Mo2.8 – 3.33.05
Ti0.65 – 1.150.9
Al0.2 – 0.80.5
Co≤ 10.3
C≤ 0.080.04
Mn≤ 0.350.1
Si≤ 0.350.1
Cu≤ 0.30.05
B≤ 0.010
P≤ 0.02—
S≤ 0.02—
Tamax, when specified separately≤ 0.05—
Febalance, typically 17–20 %balance—

Inconel 718 Stress Relieved — frequently asked

What is Inconel 718 Stress Relieved used for?

Inconel 718 Stress Relieved is typically used for gas turbine disks and blades, high-temperature fasteners and studs, turbine casings and seal rings, rocket engine injectors and manifolds, downhole drilling and completion tooling and cryogenic valve stems and springs. In short: workhorse aerospace superalloy.

What is the yield strength of Inconel 718 Stress Relieved?

Inconel 718 Stress Relieved has a typical yield strength of 740 MPa (107 ksi) and a tensile strength of 1,030 MPa (149 ksi) — stronger than 82% of nickel alloy grades. Strength varies by condition: see the 11 listed tempers.

Is Inconel 718 Stress Relieved easy to machine?

Not especially — machinability is rated poor (16/100, worse than 71% of nickel alloy grades). Machine in the solution-annealed state where possible; rigid setups, low speed (20–35 m/min carbide, 150–250 m/min ceramic), heavy positive feed, sharp tools and flood coolant to beat work hardening and notch wear.

Can Inconel 718 Stress Relieved be welded?

Yes — weldability is rated good (65/100). Very good fusion weldability by GTAW/EBW/LBW with ERNiFeCr-2 (718) filler in the annealed condition; keep heat input low, avoid restrained thick sections, and post-weld solution treat + age to restore full strength.

What surface finishes work on Inconel 718 Stress Relieved?

Not anodizable; use pickling/passivation, electropolishing, abrasive blasting or shot peening for fatigue, plus diffusion or PVD coatings for high-temperature wear.

Can Inconel 718 Stress Relieved be formed, bent or molded?

Hot work at 1010–1120 °C; cold form only from annealed stock with high tooling forces and intermediate anneals — springback and tool wear are severe.

What is the maximum service temperature of Inconel 718 Stress Relieved?

Inconel 718 Stress Relieved 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 Inconel 718 Solution Annealed and Inconel 718 Aged?

Solution Annealed is the default condition — standard stocked condition for forming, machining and welding before customer-performed aging. Aged: full-strength service condition for turbine discs, shafts, fasteners and downhole tooling to 650 °C. Yield strength is 550 MPa in Solution Annealed versus 1,170 MPa in Aged.

Can FabDigit make parts in Inconel 718 Stress Relieved?

Yes — Inconel 718 Stress Relieved is available for CNC machining, sheet metal and 3D printing with instant online pricing. Upload a STEP file to get a price and a DFM check.

Sources

  1. INCONEL alloy 718 technical bulletin — Special Metals Corporation (2007)
  2. AMS 5662 / AMS 5663 — Nickel Alloy Bars, Forgings and Rings, 718 — SAE International (2020)
  3. ASTM B637 — Precipitation-Hardening Nickel Alloy Bars, Forgings and Forging Stock for High-Temperature Service — ASTM (2018)
  4. ASTM B670 / AMS 5596 — Alloy 718 Plate, Sheet and Strip — ASTM / SAE (2019)
  5. AMS 5383 — Nickel Alloy Castings, Investment, 718 — SAE International (2018)
  6. ASM Handbook Vol.2 — Properties and Selection: Nonferrous Alloys and Special-Purpose Materials — ASM International (1990)
  7. MMPDS-17 — Metallic Materials Properties Development and Standardization — Battelle/FAA (2022)
  8. EOS NickelAlloy IN718 material data sheet — EOS GmbH (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.