The Benefits of Using Duplex Stainless Steels

The austenite and ferrite micro-structure of duplex stainless steel has a number of benefits over austenitic stainless steel. Much improved since their introduction in the 1930’s, the low nickel content of duplex stainless steels makes them a more cost effective option.

The use of nitrogen as a replacement for expensive nickel gives several advantages, including enhanced tensile properties and greater resistance to pitting and crevice corrosion, and they are twice the strength of austenitic stainless steels. Their lighter weight also makes duplex stainless steels cheaper to transport and assemble.

NeoNickel have over 30 years experience, supplying metal alloy solutions to a range of complex and challenging industries around the world. During this time the use of duplex stainless steel has grown and is a popular choice for a number of reasons including its price stability and higher strength.

Duplex Stainless Steel is used in many diverse applications including hot water and brewing tanks and is also frequently found in swimming pool structures where it is used in water temperature applications and disinfection systems.

The most widely used stainless steel is Duplex 2205 and is often referred to as the workhorse grade. It provides superior protection against corrosion than most grades of stainless steel in the majority of environments.

Who uses duplex stainless steels?

Duplex stainless steels are used in corrosive environments where they will be exposed to chloride and high temperatures and are a crucial component of the shipbuilding industry. Their ability to withstand exposure to aggressive chemicals means they are used to build most chemical tankers. Their mechanical properties can reduce the tanker’s weight by up to 10%.

There has been a significant increase in the use of duplex stainless steels in the chemical processing industry. They are an important component of the oil and gas exploration, transportation and refinement business and are a cost effective material for pollution control equipment.

Duplex stainless steel is also used in pulp and paper production and is widely utilised in mining and even nuclear plants. The steel is also a favourite of the construction industry and has been used in a variety of high profile architectural projects due to its aesthetic and structural properties.

Fabrication and welding

Easy welding and machining means that duplex stainless steel is often a cheaper option than other materials and is faster to weld than high nickel alloys. Standard rolls and dies can be used to form most shapes making duplex a cost efficient solution.

Corrosion resistance

The most outstanding feature of duplex stainless steels is their resistance to chloride stress corrosion cracking (CLSCC), a common cause of deterioration in stainless steel pipes and containers widely used by petrochemical industries.

Wrought austenitic steels are prone to stress corrosion cracking and have a tendency to crack-before-break as a result of CLSCC and as these cracks can fill with residue it is not always possible to identify a leak. NeoNickel understands that the consequences of CLSCC can be costly and catastrophic and are dedicated to creating high quality alloys that bring peace of mind to our customers.

To learn more about Duplex Stainless Steels contact a member of our team today and we’ll be happy to help you.