Nov 14 2012
Topics Covered
Introduction
Chemical Composition
Physical Properties
Other Designations
Fabrication and Heat Treatment
Machinability
Forming
Welding
Heat Treatment
Forging
Hot Working
Cold Working
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 alloys, namely cobalt-base,
nickel-base, and iron-base. All of these can be used at temperatures
above 540°C (1000°F).
Super alloy AL 600™ is a general purpose structural
engineering material that is ideal for use at elevated temperatures.
The alloy has strength, corrosion resistance, stability, and
durability, which are essential for such conditions.
The following datasheet will provide more details about super
alloy AL 600™.
Chemical Composition
The following table shows the chemical composition of super
alloy AL 600™.
| Element |
Content
(%) |
| Chromium, Cr |
14-17 |
| Iron, Fe |
6-10 |
| Manganese, Mn |
1 max |
| Copper, Cu |
0.5 max |
| Silicon, Si |
0.5 max |
| Carbon, C |
0.15 max |
| Sulfur, S |
0.015 max |
| Nickel, Ni |
72 max
|
Physical Properties
The physical properties of super alloy AL 600™ are outlined in
the following table.
| Properties |
Metric |
Imperial |
| Density |
8.47 g/cm³ |
0.306 lb/in³ |
| Melting point |
1399°C |
2550°F |
Other Designations
Equivalent materials to super alloy AL 600™ are provided in
the table below.
| AMS 5540 |
AMS 5580 |
AMS 5665 |
AMS 5687 |
ASTM B163 |
| ASTM B166 |
ASTM B167 |
ASTM B168 |
ASTM B516 |
ASTM B517 |
| ASTM B564 |
DIN 2.4816 |
MIL N-23228 |
MIL N-23229 |
MIL N-6710 |
| MIL T-23227 |
QQ W390 |
|
|
|
Fabrication and Heat
Treatment
Machinability
Traditional machining methods used for iron-based alloys can
be used for super alloy AL 600™. 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 AL 600™ can be formed using conventional methods
as it has good ductility. Powerful equipment is required.
Welding
Super alloy AL 600™ 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 should be free from oil, paint or
crayon stains.
Heat Treatment
Super alloy AL 600™ can be solution annealed at 1010°C
(1850°F) for 15 minutes and air cooled.
Forging
Forging of super alloy AL 600™ should be performed in the
range of 1232-1038°C (2250-1900°F).
Hot Working
Super alloy AL 600™ can be hot worked in the range of 1232-
871°C (2250-1600°F). It has low ductility in the range of 649-871°C
(1200-1600F), hence working in that temperature range should be avoided.
Cold Working
Super alloy AL 600™ 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.
Applications
Super alloy AL 600™ is used in the following:
- Chemical process equipment
- Heaters
- Gas turbine components
- Heat exchangers
- Heat treatment furnace components and fittings.