The difference between NIMONIC and Inconel

In the specialist metals industry, high-performance alloys play a crucial role in applications where standard materials simply would not suffice. Two of the most respected and widely utilised superalloy families are NIMONIC and Inconel. At Dynamic Metals, we're often asked about the distinctions between these exceptional materials, and below we'll shed some light on their unique properties, applications and differences.

Differences in chemical composition:

NIMONIC Alloys:

• Is based mostly on nickel (50-80%)
• Have a higher titanium content (may go up to 5%)
• Contains appreciable amounts of aluminium, often up to 4.7%
• Has a lower chromium content when compared to Inconel
• Includes cobalt to some extend for additional strength.

Inconel Alloys:

• Based on nickel and chromium (contains 50-72% nickel)
• Lower titanium content, but higher chromium (may go from 14-23%)
• Some content of iron
• May contain molybdenum and niobium largely for added strength and stability

The overall structural difference between Mechanical and Inconel is remarkable, it can be heavily felt in harsh conditions even if the difference seems like a minor one.

Performance Characteristics: When to Choose Which Alloy

Both alloy families demonstrate outstanding resistance to oxidation, corrosion and deformation at elevated temperatures. Nonetheless, their specific NIMONIC and Inconel strengths make them appropriate for different applications. 

NIMONIC Strengths: 

• Very high-temperature creep resistance is unmatched.
• Retained tensile strength at highly increased temperatures is remarkable.
• Cyclical temperature applications show improved performance.
• Thermal fatigue is withstood to a greater degree.
• Long-term stability in high-temperature environments is unparalleled.

Inconel Strengths: 

• A wider range of corrosive environments are withstood to better.
• More weldable and easier to work with.
• Typically, most grades have better treated ductility.
• Chloride stress corrosion cracking is resisted exceptionally well.
• More dominant and flexible in general in diverse industrial applications.

The variation in these performance profiles explains the tendency for these materials to be specified for different sectors and applications.

Practical Use Cases

Dynamic Metals provides both families of alloys for specific use in many markets as follows:

NIMONIC’s Typical Usage Include:

• Gas turbine parts (blades, discs, combustion chambers)
• Nuclear power plants
• Heat treatment equipment
• Industrial furnace
• Rocket engine parts
• High-performance exhaust valves

Inconel’s Typical Usage Include:

• Chemical processing heating exchangers
• Marine and seawater applications
• Oil and gas downhole apparatus
• Pollution control apparatus
• Food processing
• Pharmaceuticals
• Nuclear reactors
• Noticeable Selection Factors for Your Application

Factors needed to select NIMONIC or Inconel include the following:

Operating temperature – Usually claimed to be higher for NIMONIC

Corrosive environment – Inconel generally has a wider range of corrosive environment

Stress requirements – Certain grades of each family have different strength profiles

Construction requirements – Generally easier to shape and weld are Inconel

Pricing – The alloying elements have a direct impact on cost

Known application – Each industry has developed favourites for many reasons.

Dynamic Metals has a team of metallurgical engineers ready to design solutions to the issues and select the proper materials that suit your needs.

The Advantage with Dynamic Metals

With over three decades of experience supplying specialist metals to demanding industries, Dynamic Metals maintains extensive stocks of both NIMONIC and Inconel alloys in various forms, including sheet, bar, plate and tubular products. Our in-house processing capabilities and technical expertise ensure that we can meet the most exacting specifications.

Our metallurgists understand the nuanced differences between these alloy families and can provide detailed guidance on material selection, processing requirements and performance expectations. This consultative approach has made us the supplier of choice for aerospace, defence, energy and chemical processing industries across the UK and Europe.

Whether your application demands the exceptional high-temperature stability of NIMONIC or the versatile corrosion resistance of Inconel, Dynamic Metals has the expertise and inventory to support your requirements with confidence.

For specialist advice on selecting between NIMONIC, Inconel or any other high-performance alloys, contact our technical team today.