Inconel 718
Inconel 718 is a precipitation-hardenable nickel-chromium alloy containing significant amounts of iron, niobium, and molybdenum along with lesser amounts of aluminum and titanium. It combines corrosion resistance and high strength with outstanding weldability, including resistance to postweld cracking. The alloy has excellent creep-rupture strength at temperatures up to 700 oC (1300 oF). Used in gas turbines, rocket motors, spacecraft, nuclear reactors, pumps, and tooling.
Typical Analysis in Percentage:
Ni(+Co): 50 - 55 Cr: 17 - 21
Fe: bal Co: 1
Mo: 2.8 - 3.3 Nb(+Ta): 4.75 - 5.5
Ti: 0.65 - 1.15 Al: 0.2 -0.8
C: 0.08 Mn: 0.35
Si: 0.35 B: 0.006
Cu: 0.3
Physical Properties:
Density: 8.19 g/cm3
Melting Point/Range: 1260 - 1336 oC (2300 - 2437 oF)
J/kg ⋅ K Btu/lb ⋅ oF
Specific Heat: 435 0.104
µm/m ⋅ K µin./in. ⋅ oF
Avg. Coefficient of Thermal Expansion: 13.0 7.2
W/m ⋅ K Btu ⋅ in./ft2 ⋅ h ⋅ oF
Thermal Conductivity: 11.4 79
Electrical Resistivity: 1250 nΩ ⋅ m
Curie Temperature: -112 oC (-170 oF)
Typical Mechanical Properties:
At Room Temperature:
Ultimate Tensile Yield Strength Elongation in Elastic Modulus
Strength (0.2 % offset) 50 mm (2") (Tension)
MPa ksi MPa ksi % GPa 106 psi
1240 180 1036 150 12 211 30.6
Hardness: 36 HRC