Jul 4 2013
Topics Covered
Introduction
Chemical Composition
Physical Properties
Mechanical Properties
Thermal Properties
Fabrication and Heat treatment
Welding
Machinability
Applications
Introduction
Inconel is a group of austenitic nickel-chromium-based super alloys developed by Special Metals Corporation. Super alloys are referred to as high performance alloys that function well in environments with elevated temperatures.
INCONEL G-3 has excellent corrosion resistance to oxidizing chemicals and atmosphere as well as reducing chemicals. The high molybdenum content helps provide excellent resistance to pitting and crevice corrosion. The low carbon content helps prevent sensitization.
The following section explains in detail about super alloy INCONEL G-3.
Chemical Composition
The chemical composition of INCONEL G-3 is outlined in the following table.
|
Element |
Content (%) |
|
Nickel. Ni |
49 |
|
Chromium, Cr |
21 - 23.5 |
|
Iron, Fe |
18 - 21 |
|
Molybdenum, Mo |
6-8 |
|
Copper, Cu |
1.5 - 2.5 |
Physical Properties
The physical properties of INCONEL G-3 are tabulated below.
|
Properties |
Metric |
Imperial |
|
Density |
8.30 g/cm3 |
0.300 lb/in3 |
|
Melting point |
1260 - 1343°C |
2300 - 2449°F |
Mechanical Properties
The following table shows mechanical properties of INCONEL G-3.
|
Properties |
Metric |
Imperial |
|
Tensile strength |
≥ 621 MPa |
≥ 90000 psi |
|
Yield strength |
≥ 241 MPa |
≥ 35000 psi |
|
Elastic modulus |
199 GPa |
28900 ksi |
|
Elongation at break |
≥ 45 % |
≥ 45 % |
Thermal Properties
The thermal properties of INCONEL G-3 are tabulated below.
|
Properties |
Metric |
Imperial |
|
Thermal conductivity (@23°C/73.4°F) |
10 W/m-K |
69.4 BTU in/hr.ft².°F |
|
Thermal expansion co-efficient (@24-100°C/75.2-212°F) |
14.6 µm/m°C |
8.11 µin/in°F |
Fabrication and Heat treatment
INCONEL alloy G-3 can be readily fabricated using all the conventional methods.
Welding
Weldability of INCONEL G-3 is rated as good. It requires no post-weld heat treatment to re-attain corrosion resistance.
Machinability
INCONEL G-3 is machinable using carbide or high speed steel tools. It is recommended that the carbide tools should have high cutting speeds and feeds. In general the tools should have positive rake angles and should be operated with continuous cutting so as to avoid work-hardening of the material.
Applications
INCONEL G-3 is chiefly used in the following application areas:
-
Tank liners
-
Evaporators
-
Heat exchangers
-
In air pollution control systems
-
In damper, quencher, and outlet ducting areas
-
In the chemical and pulp and paper industries
-
In flue gas desulfurization systems such as scrubbers
-
Components in phosphoric acid manufacturing plants.