Nickel Alloy K417G-F (As fabricated)
Temper · default condition
Use as the default state for most turbine blade and vane blanks taken directly from conventional equiaxed vacuum investment casting, accepting 6 % elongation and low machinability (score 10).
Values for the F condition
Other K417G tempers and conditions
K417G is listed in 4 conditions; see the grade overview at K417G.
Compare all 4 conditionsHide
| Condition · open for datasheet | Best for | Yield MPa | Tensile MPa | Elong. % | Hardness | Conductivity |
|---|---|---|---|---|---|---|
FDefaultThis page As fabricated | Use as the default state for most turbine blade and vane blanks taken directly from conventional equiaxed vacuum investment casting, accepting 6 % elongation and low machinability (score 10). | 800 | 920 | 6 | 36 HRC | 1.4 % IACS |
Hot isostatic pressed | Pick when casting microporosity must be eliminated: hot isostatic pressing after casting raises elongation to 9 % and improves low- and high-cycle fatigue life and scatter control. | 820 | 970 | 9 | 37 HRC | 1.4 % IACS |
Solution treated and aged | Specify high-temperature solution treatment plus ageing when uniform γ′ size, microstructural stability and repeatable creep performance matter more than the extra ductility HIP would add. | 830 | 950 | 7 | 38 HRC | 1.4 % IACS |
Fine-grain investment casting | Choose fine-grain casting (grain refiner plus rapid cooling) for integral turbine wheels and high-speed disks needing higher low- to mid-temperature strength, 10 % elongation and fatigue life, but only to 900 °C. | 840 | 1,000 | 10 | 38 HRC | 1.4 % IACS |
What is K417G-F?
K417G-F is K417G in the F temper — use as the default state for most turbine blade and vane blanks taken directly from conventional equiaxed vacuum investment casting, accepting 6 % elongation and low machinability (score 10). K417G-F has a yield strength of 800 MPa (116 ksi) and a tensile strength of 920 MPa (133 ksi) — stronger than 83% of nickel alloy grades. Elongation at break is 6% and the elastic modulus is 205 GPa (29.7 Msi). K417G-F has a density of 7.8 g/cm³ (0.282 lb/in³), lighter than 96% of nickel alloy grades. It melts at 1,290°C (2,354 °F).
Advantages
- High strength — 800 MPa (116 ksi), better than 83% of nickel alloy grades
Limitations
- Limited formability — 3/100, worse than 97% of nickel alloy grades
- Hard to polish — 55/100, worse than 95% of nickel alloy grades
- Difficult to weld — 10/100, worse than 94% of nickel alloy grades
- Difficult to machine — 10/100, worse than 93% of nickel alloy grades
- Low fracture toughness — 60 MPa·√m (54.6 ksi·√in), worse than 91% of nickel alloy grades
K417G-F properties
Typical room-temperature values for K417G-F; 22 are specific to this condition. Other listed values are K417G reference data and may not represent this condition. Bars are the position among nickel alloy grades.
Physical3
K417G-F has a density of 7.8 g/cm³ (0.282 lb/in³), lighter than 96% of nickel alloy grades. It melts at 1,290°C (2,354 °F).
Mechanical16
K417G-F has a yield strength of 800 MPa (116 ksi) and a tensile strength of 920 MPa (133 ksi) — stronger than 83% of nickel alloy grades. Elongation at break is 6% and the elastic modulus is 205 GPa (29.7 Msi).
Thermal6
K417G-F is rated for continuous service to 950°C (1,742 °F). It conducts heat at 10.5 W/m·K (6.07 BTU/hr·ft·°F), worse than 73% of nickel alloy grades. Thermal expansion is 12 µm/m·K (6.67 µin/in·°F).
Electrical3
K417G-F conducts electricity at 1.4 % IACS, worse than 80% of nickel alloy grades.
Chemical & Environmental2
Corrosion resistance is good (62/100), worse than 87% of nickel alloy grades.
Sustainability4
Producing a kilogram of K417G-F takes about 230 MJ of energy and emits 15 kg of CO₂ — more than 91% of nickel alloy grades. Typical recycled content is 25%.
Manufacturability7
K417G-F's machinability is not recommended (10/100, worse than 93% of nickel alloy grades); weldability not recommended (10/100); formability not recommended (3/100).
Common Calculations5
Values are nominal handbook figures for design screening. Confirm any required mill or lot documentation when quoting.
Working with K417G-F
Is K417G easy to machine?
Extremely difficult to cut; work is dominated by grinding, EDM and low-speed, large-depth cuts with carbide or ceramic tooling. Airfoil surfaces are normally produced near net shape by precision casting.
Can K417G be welded?
Fusion weldability is very poor (Al+Ti about 10%, prone to hot cracking and strain-age cracking). Repair welding requires high preheat and a dedicated filler; vacuum brazing or diffusion bonding is the preferred repair route.
Can K417G be formed, bent or molded?
Vacuum induction melting followed by vacuum investment casting. Pouring temperature and cooling rate must be tightly controlled; the fine-grain process or HIP reduces microporosity. Not forgeable or cold formable.
What surface finishes work on K417G?
Shot peening and chemical or electrolytic core removal and cleaning are standard, followed by aluminide or MCrAlY plus thermal-barrier coatings to improve oxidation and hot-corrosion resistance.
K417G 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 |
|---|---|---|
| C | 0.13 – 0.22 | 0.17 |
| Cr | 8.5 – 9.5 | 9 |
| Cobelow the 15% of K417, key G-type modification | 9 – 11 | 10 |
| Mo | 2.5 – 3.5 | 3 |
| Algamma-prime forming element | 4.8 – 5.7 | 5.2 |
| Tigamma-prime forming element | 4.1 – 4.7 | 4.4 |
| V | 0.6 – 0.9 | 0.75 |
| Zrgrain boundary strengthening | 0.06 – 0.12 | 0.09 |
| Bgrain boundary strengthening | 0.01 – 0.02 | 0.02 |
| Feimpurity limit | ≤ 1 | — |
| Siimpurity limit | ≤ 0.5 | — |
| Mnimpurity limit | ≤ 0.5 | — |
| Simpurity limit | ≤ 0.01 | — |
| Pimpurity limit | ≤ 0.02 | — |
| Ni | balance | — |
K417G-F — frequently asked
What is K417G-F used for?
K417G-F is typically used for turbine disks, turbine blades and aero-engine hot-section castings. In short: fine-grain cast superalloy; better fatigue than coarse-grain casts; effectively unweldable.
What is the yield strength of K417G-F?
K417G-F has a typical yield strength of 800 MPa (116 ksi) and a tensile strength of 920 MPa (133 ksi) — stronger than 83% of nickel alloy grades. Strength varies by condition: see the 4 listed tempers.
Is K417G-F easy to machine?
Not especially — machinability is rated not recommended (10/100, worse than 93% of nickel alloy grades). Extremely difficult to cut; work is dominated by grinding, EDM and low-speed, large-depth cuts with carbide or ceramic tooling. Airfoil surfaces are normally produced near net shape by precision casting.
Can K417G-F be welded?
Not readily — weldability is rated not recommended (10/100). Fusion weldability is very poor (Al+Ti about 10%, prone to hot cracking and strain-age cracking). Repair welding requires high preheat and a dedicated filler; vacuum brazing or diffusion bonding is the preferred repair route.
What surface finishes work on K417G-F?
Shot peening and chemical or electrolytic core removal and cleaning are standard, followed by aluminide or MCrAlY plus thermal-barrier coatings to improve oxidation and hot-corrosion resistance.
Can K417G-F be formed, bent or molded?
Vacuum induction melting followed by vacuum investment casting. Pouring temperature and cooling rate must be tightly controlled; the fine-grain process or HIP reduces microporosity. Not forgeable or cold formable.
What is the maximum service temperature of K417G-F?
K417G-F is rated for continuous use to about 950°C (1,742 °F). Strength falls off well before that limit — check the elevated-temperature data for load-bearing parts.
What is the difference between K417G-F and K417G-FG?
F is the default condition — use as the default state for most turbine blade and vane blanks taken directly from conventional equiaxed vacuum investment casting, accepting 6 % elongation and low machinability (score 10). FG: choose fine-grain casting (grain refiner plus rapid cooling) for integral turbine wheels and high-speed disks needing higher low- to mid-temperature strength, 10 % elongation and fatigue life, but only to 900 °C. Yield strength is 800 MPa in F versus 840 MPa in FG.
Sources
- Superalloys: A Technical Guide, 2nd ed. — ASM International (2002)
- HB/GJB (K417G) (2005)
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.