Nov 12 2012
Topics Covered
Introduction
Chemical Composition
Physical Properties
Mechanical Properties
Thermal Properties
Other Designations
Fabrication and Heat Treatment
Annealing
Cold Working
Welding
Forging
Forming
Hardening
Machinability
Applications
Introduction
There are three different types of super alloys; iron-based, cobalt-based and nickel-based.
Known for their good oxidation and creep resistance, super alloys can also be strengthened by precipitation hardening, solid-solution strengthening and work hardeneing methods.
Super alloy 36™ combines low thermal expansion properties along with moderately high strength and good toughness at low temperatures. This alloy is often used in the eclectronics industry for the manufacture of bimetallic components.
The following datasheet provides an overview of super alloy 36™.
Chemical Composition
The chemical composition of super alloy 36™ is outlined in the following table.
| Element |
Content (%) |
| Iron, Fe |
60 |
| Nickel, Ni |
35-38 |
| Cobalt, Co |
≤ 1 |
| Manganese, Mn |
≤ 0.60 |
| Molybdenum, Mo |
≤ 0.50 |
| Chromium, Cr |
≤ 0.50 |
| Silicon, Si |
≤ 0.35 |
| Carbon, C |
≤ 0.10 |
| Phosphorous, P |
≤ 0.025 |
| Sulfur, S |
≤ 0.025 |
Physical Properties
The following table shows the physical properties of super alloy 36™.
| Properties |
Metric |
Imperial |
| Density |
8.11 g/cm3 |
0.293 lb/in3 |
| Melting point |
1427°C |
2600°F |
Mechanical Properties
The mechanical properties of super alloy 36™ are displayed in the following table.
| Properties |
Metric |
Imperial |
| Tensile strength (annealed prior to test) |
490 MPa |
71100 psi |
| Yield strength (annealed prior to test, @strain 0.200%) |
240 MPa |
34800 psi |
| Elongation at break (annealed prior to test) |
42.0% |
42.0% |
Thermal Properties
The thermal properties of super alloy 36™ are given in the following table.
| Properties |
Metric |
Imperial |
| Thermal expansion co-efficient (@20-100°C/68-212°F) |
1.50 µm/m°C |
0.833 µin/in°F |
| Thermal conductivity |
10.0 W/mK |
69.4 BTU in/hr.ft².°F |
Other Designations
Equivalent materials to super alloy 36™ are given below:
- ASTM B388
- DIN 1.3912
- MIL I-16598
- MIL I-23011 Class 7
Fabrication and Heat Treatment
Annealing
Super alloy 36™ is annealed by being held for 30 mins at 790oC (1450oF) for each inch of thickness. This is then followed by cooling in air. This alloy is soaked at 815oC (1500oF) to gain maximum dimensional stability and then quenched in water. The final process is to reheat this alloy to 315oC (600oF) and then cooled in air.
Cold Working
Super alloy 36™ can be swaged and cold upset in a successful manner.
Welding
Standard joining methods can be used for super alloy 36™. Usage of a similar composition alloy is recommended when a filler metal is required for the welding process.
Forging
Super alloy 36™ is heated and then cooled rapidly. The heating takes place at 1180oC (2150oF). Soaking at temperature is not recommended for this alloy.
Forming
Common forming methods can be used to readily form super alloy 36™. To obtain maximum properties, the material has to be fully annealed after the forming process.
Hardening
Super alloy 36™ cannot be hardened by thermal treatment.
Machinability
Commonly used machining methods are suitable for super alloy 36™. Good machining results can be obtained when this alloy is machined at slow speeds along with constant and positive feeds. Chips with gummy characteristics are produced by this alloy.
Applications
Super alloy 36™ is used in thermostats, radios and laser systems.