Jul 25 2013
Topics Covered
Introduction
Chemical Composition
Physical Properties
Mechanical Properties
Thermal Properties
Fabrication and Heat Treatment
Machinability
Forming
Welding
Heat Treatment
Forging
Cold Working
Annealing
Hardening
Other Designations
Applications
Introduction
Nimonic 80A alloy is a nickel-chromium alloy that is strengthened by the additions of titanium and aluminum. It has high tensile and creep-rupture properties at temperatures up to 815°C (1500°F).
The following datasheet will provide an overview of nimonic 80A alloy.
Chemical Composition
The chemical composition of nimonic 80A alloy is outlined in the following table.
|
Element |
Content (%) |
|
Chromium, Cr |
18-21 |
|
Iron, Fe |
3 |
|
Titanium, Ti |
1.8-2.7 |
|
Aluminum, Al |
1-1.8 |
|
Silicon, Si |
1 |
|
Manganese, Mn |
1 |
|
Copper, Cu |
0.2 |
|
Cobalt, Co |
0.2 |
|
Carbon, C |
0.1 |
|
Phosphorus, P |
0.045 |
|
Boron, B |
0.008 |
|
Nickel, Ni |
Balance |
Physical Properties
The following table shows the physical properties of nimonic 80A alloy.
|
Properties |
Metric |
Imperial |
|
Density |
8.19 g/cm3 |
0.296 lb/in3 |
|
Melting point |
1320-1365°C |
2410-2489°F |
Mechanical Properties
The mechanical properties of nimonic 80A alloy are displayed in the following table.
|
Properties |
Metric |
Imperial |
|
Tensile strength (Precipitation hardened) |
1250 MPa |
181000 psi |
|
Yield strength (Precipitation hardened) |
780 MPa |
113000 psi |
|
Elongation at break (Precipitation hardened) |
30% |
30% |
Thermal Properties
The thermal properties of nimonic 80A alloy are given in the following table.
|
Properties |
Metric |
Imperial |
|
Thermal expansion co-efficient (@20-100°C/68-212°F) |
12.7 µm/m°C |
7.06 µin/in°F |
|
Thermal conductivity |
11.2 W/mK |
77.7 BTU.in/hrft².°F |
Fabrication and Heat Treatment
Machinability
Nimonic 80A alloy can be machined using conventional machining techniques used for iron-based alloys.
Forming
The alloy has good ductility, and can be readily formed using all conventional methods.
Welding
Nimonic 80A alloy can be welded using conventional welding techniques such as gas-tungsten arc welding, shielded metal-arc welding and submerged-arc welding.
Heat Treatment
Nimonic 80A alloy can be heat treated at 1079°C (1975°F) for 8h and air cooled.
Forging
The alloy can be forged at temperatures ranging between 982 to 1177°C (1800 to 2150°F).
Cold Working
Cold working of this alloy can be done using standard tooling.
Annealing
The alloy can be annealed at 1079°C (1975°F) for 8 h and air cooled.
Hardening
The alloy can be hardened by cold working.
Other Designations
Other designations that are equivalent to nimonic 80A alloy include the following:
-
ASTM B637
-
DIN 2.4631
-
DIN 2.4952
Applications
The following are the list of applications of nimonic 80A alloy:
-
Gas-turbine components
-
Nuclear steam generators
-
Die-casting inserts and cores
-
Exhaust valves in internal-combustion engines.