What’s the difference between 204 and 304 stainless steel?

Have you ever wondered why some stainless steel looks similar to 304 stainless steel but is called 204 stainless steel? This article will reveal the mystery for you and help you understand the difference between 204 and 304 stainless steel.

Introduction to the Differences between 204 and 304 Stainless Steel

What are the characteristics of 204 stainless steel?

Some characteristics of 204 stainless steel include:

• Easy to manufacture: 204 stainless steel has good ductility and formability, making it easy to manufacture and weld.
• It has a low coefficient of thermal expansion, which means that when exposed to extreme temperatures, its expansion and contraction are less than other types of metal.
• It is non-magnetic, which means it is not affected by magnetic fields.
• It also has the ability to resist stress cracking, making it very suitable for use in areas under high pressure or tension.
• Corrosion resistance: 204 stainless steel has good corrosion resistance due to its high chromium content. It can resist various corrosive environments, including acids, alkalis, and chloride-containing solutions.
• Cost-effective: 204 stainless steel is a cost-effective alternative to other types of austenitic stainless steel (such as 304 or 316) due to its lower nickel content.

What is the difference between 204 and 304 stainless steel?

The main difference between 204 and 304 stainless steel is their chemical composition. Although both are austenitic stainless steels, they contain different amounts of chromium, nickel, and other elements that affect their properties.

Compared to 304 stainless steel (8-10.5%), 204 stainless steel has a lower nickel content (3.5-5.5%), making it a cost-effective alternative to 304. However, this also means that 204 stainless steel has lower corrosion resistance and mechanical properties than 304 stainless steel.

In addition, 204 stainless steel may have slight magnetic properties, while 304 stainless steel is non-magnetic. This may be important in certain applications that require non-magnetic properties.

To sum up, 204 stainless steel is a more cost-effective alternative to 304 stainless steel, but its corrosion resistance and mechanical properties are lower, and it may be slightly magnetic. The choice between the two depends on the specific needs of the application.

Corrosion Resistance of 204 and 304 Stainless Steel

In environments with low levels of corrosive media, 204 stainless steel has similar properties to 304 grade. This is why 204 grade is a cost-effective option for indoor applications with environmental temperatures. The chemical composition of the alloy makes it unsuitable for use in environments containing chloride ions. Under typical atmospheric or water-based conditions, 204 grade will not rust.

Weldability of 204 and 304 Stainless Steel

The 204 grade is a reasonably weldable alloy. However, due to the higher carbon content of 0.10%, this stainless steel is often susceptible to intergranular corrosion. This is especially true for the material in the heat-affected zone or areas that have been affected by heat. The thickness of the material also plays a role, with a thickness greater than 6mm being more susceptible to corrosion.

This is why most manufacturers recommend thorough post-welding cleaning. By performing a critical passivation treatment on the alloy, high-quality welds are further achieved. Most of the common methods can be used for welding the 304 grade. Double-certified alloys, such as 304/304L grades, can improve weldability.

Conclusion

Thank you for reading our article and we hope it can help you to know the difference between 204 and 304 stainless steel better. If you want to find more information about 204 and 304 stainless steel, we’d advise you to visit Sino Stainless Steel.

As a top supplier of stainless steel products across the world, Sino Stainless Steel provides customers with high-quality stainless steel products such as stainless steel coils, carbon steel pipes, stainless steel strips, stainless steel sheets, stainless steel wires, and stainless steel bars at a very competitive price.