300 series austenitic alloys – Checking all the boxes

Materials selection for any piece of equipment or a process system is rarely a simple task, unless you are exactly replicating something successful. Often engineers will have a checklist to help them narrow down the choices, eliminating groups of materials that are not suitable for various reasons. Austenitic 300 series stainless steels containing 7-35% nickel will have most if not all of the boxes checked for being suitable where a stainless steel is desired.

Codes and standards

300 series alloys are in every stainless steel application standard, for pressure vessels, tanks, food and pharmaceutical equipment, structural use, etc.


The 300 series alloys have outstanding ductility, which means outstanding formability. That is important in deep drawing and for producing complex shapes. As ductility decreases with increasing strength, the duplex grades have decreased formability, although still suitable for most forming operations.

Higher temperature properties

The strength of the austenitic structure shines compared to other families, especially in the creep strength temperature range. A major consideration though is how the properties will transform with time. Many stainless steel alloys become brittle in certain temperature ranges, but the higher nickel austenitic alloys are most often the best choice.

Corrosion resistance

There are many different 300 series alloys available for general and specific applications, ranging from the 18/8 versions to alloys that compete with some of the nickel alloys.


While all stainless steels are recyclable, the 300 series are more likely to be recycled because they have a higher inherent value at end-of-life.

Ambient temperature strength

300 series alloys have moderate strength, so specify dual certified grades 304/304L and 316/316L where necessary. These dual grade alloys often contain a small nitrogen addition, however the nitrogen-alloyed versions (e.g. 304N) are slightly stronger. If high strength is needed, consider a slightly cold-worked 300 series alloy or a duplex alloy. If no welding is involved and relatively low corrosion resistance needed, consider a greater cold worked 300 series alloy, or a martensitic or precipitation hardening stainless steel. 

Low temperature properties

The wrought austenitic alloys remain tough (that is do not become brittle) down to very low temperatures, some even down to near absolute zero. All the other families have a much higher ductile-to-brittle transition temperature.


Of all the families of stainless steels, the 300 series are the most commonly and most easily welded, maintaining their mechanical properties and corrosion resistance.


The 300 series are generally available in the most product forms, with more sizes, and thicknesses from foil to extremely thick.


There are many applications where the 300 series alloys have demonstrated they are the lowest overall cost.

While the other families of stainless steels have their applications, the 300 series, with nickel as a key ingredient, continue to be by far the most popular and most adaptable.. 

The cover picture above shows a large vessel with many different nozzles, including a half pipe coil, in 300 series stainless steel with hygienic requirements for the production of personal care products. 

The Nickel Institute offers a free technical inquiry service to help you when using nickel -  

Many publications for users and specifiers are also available free-of-charge on our website.

Of particular relevance is The Nickel Advantage, Nickel in Stainless Steels, available in EnglishFrenchJapanese and Chinese

The Nickel Institute offers a free technical inquiry service to help you when using nickel -
The Nickel Institute offers a free technical inquiry service to help you when using nickel -