Incoloy 925 Round Bars vs Incoloy 825 – What’s the Difference?

Choosing the right material for your industrial application is a crucial task that requires careful consideration of several factors, such as resistance to corrosion and high-temperature environments, durability, and cost-effectiveness. Regarding high-performance alloys, Incoloy 925 and Incoloy 825 are both popular choices, thanks to their impressive properties and versatility. However, which one is better suited for your specific project? In this blog post, we’ll compare the features of Incoloy 925 round bars and Incoloy 825 to help you make an informed decision.

What is Incoloy 925 Round Bars and Incoloy 825?

Incoloy 925 is an age-hard enable nickel-iron-chromium alloy with high levels of molybdenum and copper for increased corrosion resistance. Incoloy 825, on the other hand, is a nickel-iron-chromium alloy containing significant amounts of both molybdenum and copper.

In terms of composition, Incoloy 925 has higher molybdenum (18% vs 2%-3%) and lesser amounts of chromium (23% compared to 19%-24%). This results in superior strength when compared to Incoloy 825. In addition, Incoloy 925 also exhibits better heat-resistant properties that enable it to tolerate temperatures up to 1600°F or 870°C. On the contrary, due to its lower chromium content, Incoloy 825 can only handle temperatures up to 1200°F or 650°C before experiencing loss in its mechanical properties.

Lastly, because they are often used in marine environments where corrosion resistance is essential for the successful operation of equipment or structures over time – particularly at high temperatures – both materials offer good protection against pitting and crevice attack from seawater environments as well as excellent weldability by many processes – MIG/TIG welding included!

Difference Between Incoloy 925 Round Bars vs Incoloy 825

Chemical composition

Incoloy 925 and Incoloy 825 are nickel-based alloys with similar chemical compositions but differ in certain key elements. Incoloy 925 has a higher amount of molybdenum and copper, giving it superior corrosion resistance in extremely harsh environments. In contrast, Incoloy 825 contains more iron and chromium, which makes it an excellent choice for applications that require high strength and resistance to oxidation and acid attack.

Incoloy 925 and 825 round bars contain nickel, chromium, and iron as primary components. The difference lies in their chemical composition: Incoloy 925 contains higher levels of nickel (19%-23%) and molybdenum (3%-4.5%), while the levels of nickel (20-23%) and molybdenum (2.5-3.5%) are lower in Incoloy 825. This difference gives the two materials distinct advantages when used for different applications, such as corrosion resistance, strength at high temperatures, ductility, weldability etc., making them both popular choices in industries where these qualities are desired.

Physical Properties

Incoloy 925 is known for its outstanding mechanical properties, including high tensile strength, excellent fatigue resistance, and good impact strength. It also exhibits good weldability and can be easily fabricated into different shapes and sizes. On the other hand, Incoloy 825 has a low thermal expansion coefficient, making it highly resistant to thermal stresses and cracking. Additionally, it has good ductility and low magnetic permeability, which makes it suitable for applications that require good electromagnetic properties.

Corrosion Resistance

Both Incoloy 925 and Incoloy 825 offer excellent resistance to corrosion in a wide range of acidic and alkaline environments, including seawater, sulfuric acid, nitric acid, and hydrochloric acid. However, Incoloy 925 is particularly effective in resisting corrosion caused by sulfuric acid, hydrofluoric acid, and hydrogen sulfide. Incoloy 825, on the other hand, is highly resistant to stress-corrosion cracking, pitting, and crevice corrosion in highly oxidizing environments.


Incoloy 925 round bars are widely used in applications that require high strength, such as oil and gas production, chemical processing, and nuclear power plants. It’s also a popular choice for making components in marine and military environments. In contrast, Incoloy 825 is often used to produce heat exchangers, piping systems, and other equipment in the chemical and petrochemical industries. It’s also suitable for making components in the marine and aerospace industries.


Incoloy 825 is generally more cost-effective than Incoloy 925 because it is a nickel-iron-chromium alloy containing titanium and copper, which is less expensive to produce compared with the higher levels of molybdenum found in Incoloy 925. Incoloy 825 has better corrosion resistance in chloride media and lower thermal expansion properties, making it well-suited for many corrosive applications.

The cost of using either Incoloy 925 or Incoloy 825 depends on the application, the project size, and the material’s market availability. As a general trend, Incoloy 925 is more expensive than Incoloy 825 due to its higher amount of alloying elements.


In summary, both Incoloy 925 and Incoloy 825 offer excellent properties for various industrial applications. While Incoloy 925 excels in resisting corrosion in harsh environments, Incoloy 825 is better suited for applications that require high strength and resistance to oxidation and acid attack. Ultimately, the best choice for your project will depend on your specific requirements and budget. By understanding the differences between the two alloys, you can make an informed decision and select the most suitable material for your needs.

Incoloy 925 Round Bars vs Incoloy 825 – What’s the Difference?

by AB Steel time to read: 3 min