321 Stainless Steel – Data Sheet, Applications, Hardening

The material 321 is an austenitic stainless steel with a titanium alloy, which stabilizes the metal against chromium carbide formation. For this reason, 321 can be welded with excellent resistance to intergranular corrosion. The material is also known by the designation EN 1.4541 and the material number X6CrNiTi18-10. It belongs to the V4A grades and is classified as a chromium-nickel steel. 321 is known for its excellent corrosion resistance, cold forming and weldability. Due to the titanium alloy, the material is more expensive to purchase compared to other V4A steels and is therefore not one of the widely used stainless steels in industry. Nevertheless, thanks to its good properties, it is used in many demanding areas.

321 Data Sheet

According to DIN EN 10088-3, the chemical composition of 321 is as follows:

≤ 0.08%≤ 1 %≤ 2 %≤ 0.045%≤ 0.03%17.5 – 19%9 – 12%5*C – 


The minimum amount of titanium alloy is based on the carbon content in the metal. Titanium must be present in about five times the mass of carbon to form titanium carbide. In terms of chemical composition, it is similar to austenitic material 316Ti, among others, although molybdenum is still found in the latter as a significant alloying element. Molybdenum increases corrosion resistance and acts as a stabilizer with good thermophysical properties. Further, the material is characterized by average mechanical properties. Machining should be carried out with high-speed steel because of its tendency to work hardening.

The material 321 also has similarities with the widely used stainless steel 304 (1.4301). It is a titanium-stabilized variation of the popular grade and has a similarly high chromium-nickel content.

Applications of 321

321 can be used in a wide range of industries, such as:

The material is especially suited for applications at elevated temperatures. For maximum corrosion resistance, 321 must be water quenched or fully annealed.

In Europe, austenitic stainless steel is used less frequently. Here, the material 316Ti is preferred, as it exhibits similar material properties and has been used for many components for decades. In North America, on the other hand, 321 is more widespread and is used for many applications.

The material 321 is suitable for applications in fresh water, but should not be used in salt water. Tolerance to salt and chlorine concentrations is low.

Hardening of 321

Although the metal has high corrosion resistance, it can be overworked in the long term in many applications. In order to meet the high demands of the components even after many years, our BORINOX® process is the ideal solution. Thanks to the robust diffusion coatings, we effectively increase the service life of stainless steel components. Partial treatment of components is also possible with BORINOX®.

Contact us here if you would like to harden your 321 steel or any other stainless steel. We are looking forward to your inquiry!