How to Select and Use 431 Stainless Steel Round Bar for Aerospace Industry

The aerospace industry is a demanding sector requiring high-quality materials capable of withstanding extreme conditions. A stainless steel round bar is a preferred choice for aerospace applications because of its excellent resistance to high temperatures, corrosion, and oxidation. Among the different types of stainless steel materials, 431 stainless steel is preferred for its high strength, durability, and corrosion resistance. If you are an aircraft manufacturer, engineer or designer looking to use a 431 stainless steel round bar for your aerospace application, this blog post is for you. In this blog, we will explore how to select and use 431 stainless steel round bars for the aerospace industry.

What is a 431 Stainless Steel Round Bar?

431 Stainless Steel Round Bar is a popular material in the aerospace industry due to its excellent combination of corrosion resistance, strength, and heat resistance. It’s been approved by numerous authorities as an acceptable material for use in aircraft and other aerospace applications. Its high levels of chromium and nickel make it an especially attractive choice for environments with corrosive elements, while its relative ease of machinability makes it ideal for rapid prototyping or production processes. Its low carbon content helps retain its strength after welding, ensuring there are no mechanical issues during operation. Furthermore, its ability to resist heat shock makes it suitable even when exposed to extreme temperature fluctuations over time. All these features make the 431 Stainless Steel Round Bar a great option when searching for metals that can be used in aerospace applications.

431 stainless steel is a martensitic stainless steel alloyed with chromium, providing high strength and corrosion resistance. It contains elements like nickel, copper, and molybdenum and has a high toughness that can be retained up to 600°C. This makes 431 stainless steel a preferred material for high strength, corrosion, and heat resistance applications.

Selecting the Right 431 Stainless Steel Round Bar

When selecting 431 stainless steel round bars for the aerospace industry, there are several factors you need to consider. Choosing the right 431 stainless steel round bar for your project requires careful consideration of its features. It is a high-chromium stainless steel that combines exceptional toughness, corrosion resistance, and heat resistance with excellent hardness. These include the size, grade, and finish of the bar. Bars can be purchased in different sizes, with common sizes ranging from 1/16″ up to 24″. The grade of 431 stainless steel you select will depend on the application. We recommend selecting 431 stainless steel with a low carbon content for high-temperature applications. High carbon content increases the risk of intergranular corrosion and can cause a reduction in toughness. The bar’s finish is also important, with options like turned, ground, or forged finishes available. When properly hardened and tempered, it can be readily welded using the most common techniques, making this grade one of the best all-around choices for a variety of industrial applications, including shafts, valves, pins, fasteners, bolts, nuts, etc., where superior strength combined with moderate levels of corrosion are desired such as petrochemical processing equipment working under salty environments or aggressive solutions like bleaches or acids used in food production plants where its low magnetic permeability provides additional product protection against damage caused by accidental contact with magnets commonly found near their machinery.

Using 431 Stainless Steel Round Bars for the Aerospace Industry

Once you have selected the appropriate 431 stainless steel round bar for your aerospace application, there are certain guidelines that you should follow when using it. We recommend treating the material carefully to avoid surface damage or stress corrosion cracking. When machining 431 stainless steel, you must use a low cutting speed and high feed rate to prevent heat buildup. Overheating can lead to discolouration or scaling of the surface, resulting in cracks and fissures. When heat-treating 431 stainless steel, it is important to preheat slowly and evenly to avoid the warping of the material.

It is also crucial to ensure that the 431 stainless steel round bar is clean and contaminant-free before using it. Any oil, grease, or dirt left on the surface can lead to corrosion and material deterioration. Proper packaging, handling, and storage of the bar can also significantly impact its properties and longevity.


431 Stainless steel is a popular material for the aerospace industry due to its high strength, corrosion resistance, and durability, making it an ideal choice for applications that require high performance and longevity. When selecting and using a 431 stainless steel round bar, it is important to consider factors such as size, grade, and finish, while following guidelines for machining, heat treatment, and maintenance. By doing this, you can ensure that your aerospace application will meet the highest quality, reliability, and safety standards.