Stainless Steel 316 vs 321- What’s the Difference

Stainless Steel 316 vs 321

When choosing the right stainless steel for your project, knowing which one is right for you can take time. Two of the most commonly used stainless steel alloys are 316 and 321. While both alloys are similar, there are some important differences to consider. In this blog post, we will compare 316 and 321 stainless steel characteristics to help you choose the right one for your needs.

Difference Between Stainless Steel 316 and 321

Chemical Composition

Stainless steel 316 and 321 are austenitic stainless steels containing chromium, nickel, and small amounts of carbon. However, 316 contains molybdenum, while 321 contains titanium. The molybdenum in 316 provides better corrosion resistance to chloride environments than titanium in 321. On the other hand, titanium provides excellent resistance to carbide precipitation during welding in high-temperature applications.

Corrosion Resistance

Both stainless steel alloys are highly resistant to corrosion, but 316 performs better in salt or chloride environments. This is due to the presence of molybdenum, which helps to prevent chloride ion corrosion. While 321 also offers good resistance to corrosion, it is not recommended for use in environments with high chloride levels.


Both 316 and 321 stainless steel are easy to weld. However, 321 has better weldability due to its low carbon content. The low carbon content reduces the risk of carbide precipitation during welding, which can cause intergranular corrosion.

Heat Resistance

Stainless steel 321 is ideal for use in high-temperature applications. It offers excellent resistance to oxidation and scaling up to 900°C. Additionally, 321 has a higher creep and stress rupture strength than 316 stainless steel. While 316 is also suitable for high-temperature applications, it is not as heat resistant as 321.


The cost of stainless steel 316 is generally lower than 321. This is because 316 is more widely available and less expensive to produce. However, the cost difference must be more significant to make a huge difference in most projects.


Stainless steel 316 and 321 are excellent choices for various applications. Both are austenitic stainless steels with excellent corrosion, weldability, and heat resistance. The main difference between the two alloys is their chemical composition. 316 contains molybdenum, which provides better resistance to chloride environments, while 321 has titanium, which offers excellent resistance to carbide precipitation during welding in high-temperature applications. Ultimately, the choice between the two alloys will depend on the specific needs of your project. Before deciding, consider factors such as corrosion resistance, heat resistance, and cost.

Minal Jogale

Minal Jogale

Recent Posts