Nov 15 2012
Topics Covered
Introduction
Chemical Composition
Physical Properties
Fabrication and Heat Treatment
Machinability
Forming
Welding
Cold Working
Annealing
Applications
Introduction
Super alloys are also called high performance alloys. They have the capacity to function under very high temperatures and extreme mechanical stress, and also where high surface stability is required. They have good creep and oxidation resistance.
Super alloys contain many elements in a variety of combinations so as to achieve the required result. Strengthening of super alloys is performed by solid-solution hardening, work hardening, and precipitation hardening methods.
There are three types of super alloys, namely cobalt-base, nickel-base, and iron-base. All of these can be used at temperatures above 540°C (1000°F).
Super alloy 214 is a nickel-base alloy with good oxidation resistance, high temperature resistance, and high strength.
The following datasheet will provide more details about super alloy 214.
Chemical Composition
The following table shows the chemical composition of super alloy 214.
|
Element |
Content (%) |
|
Carbon, C |
0.08 max |
|
Manganese, Mn |
0.5 max |
|
Silicon, Si |
0.2 max |
|
Zirconium, Zr |
0.1 max |
|
Nickel, Ni |
Remainder |
Physical Properties
The physical properties of super alloy 214 are outlined in the following table.
|
Properties |
Metric |
Imperial |
|
Density |
8.05 g/cm³ |
0.291 lb/in³ |
|
Melting point |
1371°C |
2500°F |
Fabrication and Heat Treatment
Machinability
Traditional machining methods used for iron-based alloys can be used for super alloy 214. During high-speed operations such as turning, grinding, or milling, it is recommended that water-based coolants are used. The use of heavy lubricants while drilling, tapping, broaching or boring is suitable. In cases where turning with a continuous cut is performed, carbide tools are suitable.
Forming
Super alloy 214 can be formed using conventional methods as it has good ductility. Powerful equipment is required.
Welding
Super alloy 214 is weldable using all the conventional methods. Some of the commonly used methods are gas-tungsten arc welding, shielded metal-arc welding, gas metal-arc welding and submerged-arc welding. It is recommended that matching alloy filler metal should be used. Before the welding process begins, the surface to be welded should be cleaned and free from oil, paint or crayon stains.
Cold Working
Super alloy 214 can be cold worked using conventional tooling. To minimize galling and provide a neat finish, soft die materials containing bronze and zinc alloys are recommended. However, the life of the die is short.
Annealing
Super alloy 214 can be annealed at 1093°C (2000°F) and then quickly air cooled.
Applications
Super alloy 214 is used in the following:
-
Gas turbine components
-
Industrial furnace components
-
Gas fired radiant heating tubes.