Nimonic 80A

Nimonic 80A is a high-strength nickel-chromium alloy with excellent corrosion resistance and thermal stability, widely used in aerospace, energy, and high-temperature applications.

About Nimonic 80A Superalloy

Name and Equivalent Name

Nimonic 80A, also identified by UNS N07080, is referenced in several standards: ASTM B637, DIN/EN 2.4952 (NiCr20TiAl), BS HR 1, GB/T 14992 (GH4033), and AMS 5828. It is also known as Nickel-Chromium Alloy 80A.

Nimonic 80A Basic Introduction

Nimonic 80A is a nickel-chromium alloy with high mechanical strength and thermal fatigue resistance, making it ideal for high-temperature applications. This alloy is designed to withstand extreme operating environments without significant loss of strength or oxidation resistance.

Primarily used in aerospace and energy sectors, Nimonic 80A is employed in turbine blades, valves, exhaust components, and nuclear reactors. It offers long service life and consistent performance even under cyclic thermal stress, ensuring reliability in mission-critical operations.

nimonic-80a-superalloy-castings-cnc-machining-factory

Alternative Superalloys of Nimonic 80A

For applications requiring similar high-temperature performance, Inconel 718 and Hastelloy X are alternatives to Nimonic 80A, offering excellent creep and fatigue resistance. Nimonic 75 is another option, providing good thermal stability but slightly lower strength.

When oxidation resistance is paramount, Nimonic 90 may be preferred for turbine applications. Hastelloy C and Incoloy 800 are suitable alternatives for environments with aggressive corrosion. Selection depends on the operating temperature, environmental exposure, and stress conditions.


Nimonic 80A Design Intention

Nimonic 80A is engineered to deliver high mechanical strength and thermal fatigue resistance in high-temperature environments. Its chromium content provides excellent oxidation resistance, while titanium and aluminum enhance the alloy’s strength through precipitation hardening.

The alloy’s primary design goal is to perform reliably under continuous thermal cycling, particularly in jet engines, turbines, and exhaust systems. Nimonic 80A offers stable mechanical properties across various temperatures, ensuring minimal deformation and long operational life.


Nimonic 80A Chemical Composition

The chemical composition of Nimonic 80A ensures a balance between strength, oxidation resistance, and thermal stability. Nickel provides toughness, while chromium enhances corrosion resistance. Titanium and aluminum facilitate precipitation hardening, increasing the alloy’s strength.

Element

Composition (%)

Nickel (Ni)

70.0 min

Chromium (Cr)

18.0 – 21.0

Titanium (Ti)

1.8 – 2.7

Iron (Fe)

3.0 max

Aluminum (Al)

1.0 – 1.8

Others

Trace elements


Nimonic 80A Physical Properties

Nimonic 80A’s physical properties make it suitable for thermal stability applications and high mechanical strength at elevated temperatures.

Property

Value

Density

8.31 g/cm³

Melting Point

1380°C

Thermal Conductivity

12.1 W/(m·K)

Modulus of Elasticity

208 GPa


Metallographic Structure of Nimonic 80A Superalloy

Nimonic 80A features a face-centered cubic (FCC) crystal structure, typical of nickel-based alloys, ensuring high strength and excellent thermal fatigue resistance. The presence of aluminum and titanium precipitates enhances its mechanical properties by forming intermetallic phases.

Even after extended exposure to high temperatures, the alloy maintains microstructural stability, preventing grain growth and phase transformation. This consistency ensures that Nimonic 80A retains its mechanical strength and resistance to creep under extreme conditions.


Nimonic 80A Mechanical Properties

The mechanical properties of Nimonic 80A allow it to maintain performance under high stress and temperature. It offers excellent creep resistance, fracture toughness, and long creep-rupture life.

Property

Value

Tensile Strength

930-1035 MPa

Yield Strength

690-760 MPa

Hardness

Rockwell C35-45

Elongation

20-30%

Elastic Modulus

~210 GPa

Creep Strength

High at 815°C

Creep Rupture Life

>10,000 hours at 815°C

Fatigue Strength

~380-450 MPa


Key Features of Nimonic 80A Superalloy

  1. High-Temperature Strength Nimonic 80A provides excellent mechanical strength up to 815°C, ensuring durability in demanding applications like jet engines and gas turbines.

  2. Oxidation and Corrosion Resistance With 18-21% chromium content, Nimonic 80A offers exceptional resistance to oxidation and corrosion, making it suitable for harsh environments.

  3. Thermal Fatigue Resistance The alloy performs reliably under continuous thermal cycling, reducing the risk of fatigue cracking in high-temperature systems such as exhaust components.

  4. Creep and Rupture Resistance Nimonic 80A maintains its mechanical integrity over prolonged exposure to high temperatures, offering over 10,000 hours of creep-rupture life at 815°C.

  5. Precipitation Hardening for Increased Strength: The addition of titanium and aluminum allows Nimonic 80A to undergo precipitation hardening, increasing its strength for demanding aerospace and energy applications.

Nimonic 80A Superalloy’s Machinability

Nimonic 80A can be used in Vacuum Investment Casting due to its high-temperature strength and oxidation resistance, which ensures precise casting of complex aerospace and energy components.

Single Crystal Casting is not ideal for Nimonic 80A, as the alloy’s metallurgical design does not support single-crystal formation, which is necessary for advanced turbine applications.

The alloy performs well in Equiaxed Crystal Casting, ensuring isotropic mechanical properties and being suitable for parts like turbine blades and exhaust components.

Nimonic 80A is compatible with Superalloy Directional Casting, enhancing grain structure along the stress axis, which improves its high-temperature mechanical performance.

It is unsuitable for Powder Metallurgy Turbine Disc production due to its composition, which is optimized for cast and forged components rather than powder-based methods.

Nimonic 80A can be used in Superalloy Precision Forging to create high-strength components such as valves and turbine parts that require mechanical precision.

The alloy is not recommended for Superalloy 3D Printing due to its high melting point and complex structure, which complicates powder-based manufacturing processes.

It performs excellently in CNC Machining, where its moderate hardness and thermal stability allow for efficient machining without compromising dimensional precision.

Superalloy Welding is possible with Nimonic 80A, but precise techniques are required to avoid cracking during the welding process, especially under thermal stress.

Nimonic 80A responds well to Hot Isostatic Pressing (HIP), enhancing its mechanical properties by reducing internal porosity and improving fatigue resistance for critical applications.


Nimonic 80A Superalloy Applications

In Aerospace and Aviation, Nimonic 80A is used for turbine blades, exhaust systems, and combustion chamber components, where high-temperature strength and oxidation resistance are critical.

In Power Generation, the alloy is employed in gas turbines and heat exchangers, delivering long-lasting performance under thermal fatigue.

The Oil and Gas industry benefits from Nimonic 80A’s resistance to high-temperature corrosion, making it ideal for valves, flanges, and pipelines exposed to extreme conditions.

For Energy applications, Nimonic 80A ensures reliability in high-temperature boilers, turbines, and industrial furnaces, contributing to operational efficiency.

In the Marine sector, Nimonic 80A is used for exhaust systems and propulsion components, offering excellent corrosion resistance in saltwater environments.

Mining operations rely on Nimonic 80A for components such as drilling tools and pump housings, where wear resistance and high strength are essential.

In Automotive, the alloy uses high-performance exhaust systems and turbochargers, offering durability and heat resistance.

The Chemical Processing industry uses Nimonic 80A for reactors and heat exchangers thanks to its excellent corrosion and oxidation resistance in aggressive chemical environments.

In pharmaceutical and food processing, Nimonic 80A ensures the safety and reliability of high-temperature valves and heat exchangers.

Military and Defense applications include jet engines and missile components, where the alloy’s mechanical strength and resistance to extreme environments are critical.

In Nuclear industries, Nimonic 80A is used in reactor components and heat exchangers, offering high-temperature stability and corrosion resistance in radiation-exposed environments.


When to Choose Nimonic 80A Superalloy

Nimonic 80A is the right choice for applications where high-temperature strength, thermal fatigue resistance, and oxidation resistance are essential. It is ideal for custom superalloy parts used in aerospace, power generation, and energy systems. Its ability to withstand thermal cycling makes it a reliable material for turbine blades, valves, and exhaust systems.

If your project requires precision components that can maintain mechanical integrity under continuous high-temperature exposure, Nimonic 80A offers a dependable solution. It is particularly effective in environments where corrosion and oxidation resistance are critical, such as chemical processing plants and marine systems. Additionally, it performs well under mechanical stress, ensuring extended service life and minimal maintenance. Explore our custom superalloy parts service to see how Nimonic 80A can fit your specific industry needs.

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