When it comes to choosing the right type of stainless steel for your project, it can often feel overwhelming with all the options available. Stainless Steel 321 and 347 are popular choices, but what sets them apart? In this blog post, we’ll dive into the differences between the two so you can make an informed decision for your next project.
Difference Between Stainless Steel 321 and 347
Chemical Composition
Stainless Steel 321 and 347 are austenitic stainless steels containing chromium and nickel. However, their chemical composition differs. Stainless Steel 321 has titanium added, which provides resistance to intergranular corrosion. On the other hand, Stainless Steel 347 has columbium added, improving intergranular corrosion resistance over 321.
Heat Resistance
321 and 347 stainless steel are designed to perform well in high-temperature applications. However, Stainless Steel 321 is preferred for its superior performance at high temperatures and durability in cyclic environments. 321 can withstand temperatures up to 1500°F. Stainless Steel 347 can also perform well at high temperatures, up to 1600°F. However, it is not recommended for cyclic environments.
Weldability
Stainless Steel 321 is preferred for its excellent weldability, ability to be welded to other metals, and resistance to high-temperature oxidation. Stainless Steel 347, on the other hand, has limitations to its welding capabilities. It can only be welded using a low-carbon welding electrode and may require post-weld annealing.
Cost
Stainless Steel 321 is generally considered more affordable than Stainless Steel 347, but this can vary depending on the supplier and the specifics of your project. Generally, the price difference is generally due to 347’s more complex chemical composition and superior resistance to intergranular corrosion.
Common Applications
Stainless Steel 321 and 347 are commonly used in high-temperature environments, such as aerospace and power generation industries. However, Stainless Steel 321 is often used in exhaust systems, where it can withstand the cyclic heating and cooling involved. Stainless Steel 347 is commonly used in chemical processing and pharmaceutical industries because of its superior corrosion resistance.
Conclusion:
When it comes to choosing between Stainless Steel 321 and 347, it ultimately comes down to the specific requirements of your project. Stainless Steel 347 may be your best bet if you require superior resistance to intergranular corrosion. However, if you need a cost-effective solution that can withstand high-temperature environments, Stainless Steel 321 may be the way to go. Either way, both types of stainless steel offer exceptional performance and durability for a wide range of industrial applications. Partnering with an experienced supplier can also ensure you get the right material for your project.
