The Difference Between 2205 Duplex Stainless Steel And 304, 316

Duplex 2205 stainless steel is a type of stainless steel, which is different from austenitic 304/316 stainless steel, has better mechanical properties, chemical properties, and higher prices. Duplex stainless steel (DSS) is mainly divided into duplex 2205 pipes and fittings, flanges, etc. Among them, duplex steel flanges can be made of 2205 on one side and 316 / 316L on the other.

In the following, we will analyze the main differences between the duplex 2205 stainless steel and 304 and 316 austenitic stainless steel.

First of all, let’s look at the yield strength.

Duplex steel is more than double the ordinary austenitic stainless steel and has sufficient plastic toughness required for forming. The wall thickness of the storage tank or pressure vessel made of duplex stainless steel is 30-50% less than the commonly used austenite, which is conducive to reducing costs.

The second is corrosion resistance. Duplex steel has excellent resistance to stress corrosion cracking. Even the duplex stainless steel with the lowest alloy content has higher resistance to stress corrosion cracking than austenitic stainless steel.

Finally, mechanical properties. Duplex steels have higher energy absorption capacity than austenitic stainless steels under dynamic or static loading conditions. This has a significant advantage for duplex components in coping with sudden accidents such as collisions and explosions.

Compared with austenitic stainless steel, duplex stainless steel also has certain defects:

• 1. The universality and multi-facetness of the application are not as good as austenitic stainless steel, for example, its use temperature must be controlled below 250 degrees Celsius.
• 2, its plastic toughness is lower than austenitic stainless steel, cold, hot processing technology and forming performance is not as good as austenitic stainless steel.
• 3. There is a medium-temperature brittle zone, and the process system of heat treatment and welding needs to be strictly controlled to avoid the occurrence of harmful phases and damage to performance.

In general, 2205 duplex stainless steel is an excellent stainless steel material. It can be used in places with special requirements on acid, alkali, environment and stress. When purchasing, you need to pay attention to the above points and choose appropriately.