Stainless Steels

Due to it consisting of approximately 50% ferritic microstructure, duplex stainless steels are considered magnetic.

Austenitic stainless steels are non-magnetic, whereas Ferritic, Duplex and Martensitic stainless steels are all magnetic.

Pitting corrosion is the most common form of corrosion that can occur on stainless steels.

Stainless steel will corrode if the conditions are suitable severe, but they are significantly more corrosion resistant than carbon steels.

Stainless steel is used in a plethora of applications, where alternative metals would not be suitable for either practical or aesthetic reason

The generally accepted view is that stainless steels were developed by Harry Brearley (Sheffield, UK) around 1911.

Ferralium is the world’s first super duplex stainless steel developed by Langley Alloys in 1967.

Super duplex stainless steels benefit from a combined microstructure of austenite and ferrite, which provides an optimum mix of properties.

The difference in properties between austenitic and duplex stainless steels is explained by their different microstructures.

Duplex stainless steels are based around a composition of 22% chromium, whereas super duplex stainless steels are based around 25%.

Duplex, Super Duplex and Hyper Duplex have a combination of austenitic and ferritic microstructures, approximately 50:50.

There are a number of different austenitic stainless steels, the most common being the 300 series (304/316) produced in large volumes.