Alloy 718

Energy Steel Industrial Co., Ltd.
Steel Fabrication,Special Steel,Nickel Alloy Steel Tube

Alloy 718

Inconel® 718 tubing was initially developed for the aerospace industry but its excellent strength and corrosion resistance were recognised by the oil industry and it is now widely used in this field as well.

Inconel® 718 tubing is a nickel-chromium alloy which can be heat-treated to give high strength, good corrosion resistance, ease of formability and which can be welded with good resistance to strain age cracking. The alloy can be used at temperatures up to 700ºC.

For aerospace and power generation, Inconel® 718 tubing is heat treated such that the hardness does not exceed 40HRC which is the maximum allowed by NACE MR-01-75/ ISO 15156: 3 to prevent stress corrosion cracking. The major applications in this field are Valves and precision tubing.

Alloy 718 for aerospace and power generation is heat treated to give maximum strength and high creep resistance with typical hardness values exceeding 42HRC. The major applications are components for gas turbines, aircraft engines, fasteners and other high strength applications.

Product Description
Available tube product forms
Straight
Seamless

Typical Applications
Heat exchangers
Well head completion equipment
Mandrels
Valves

Typical manufacturing specifications
AMS 5589
AMS 5590
Also individual customer specifications.

Industries predominantly using this grade
Aerospace
Oil and gas
Nuclear and power
Technical Data

Mechanical Properties

Temper

Solution-treated

Tensile Rm

155

ksi (Max)

Tensile Rm

1069

MPa (Max)

R.p. 0.2% Yield

95

ksi (Max)

R.p. 0.2% Yield

655

MPa (Max)

Elongation (2” or 4D gl)

30

% (min)


Physical Properties (Room Temperature)

Specific Heat (0-100°C)

435

J.kg-1.°K-1

Thermal Conductivity

11.4

W.m -1.°K-1

Thermal Expansion

13

μm/μm/°C

Modulus Elasticity

200

GPa

Electrical Resistivity

1.32

Ohm-cm

Density

8.19

g/cm3


Chemical Composition (% by weight)


Element

Min

Max

C

-

0.08

Si

-

0.35

Mn

-

0.35

P

-

0.015

Al

0.2

0.8

B

-

0.6

Co

-

1

Cr

17

21

Cu

-

0.3

Fe

Balance

Mo

2.8

3.3

Nb

4.75

5.5

Ni

50

55

Ti

0.65

1.15