Super Duplex

UNS S32760 is a super duplex stainless steel, based around a chromium content of 25%, that is also referred to as DIN 1.4501 and ASTM A182 F55 (when supplied as solid bars). The grade known as S32760 was originally developed by Mather & Platt and marketed as Zeron 100. Mather & Platt was a UK-based […]

DIN 1.4462 is a duplex stainless steel based around a 22% chromium content. Developed in the 1930s for application in paper and pulp manufacture, duplex stainless steels have twice the strength and provide a significant uplift in corrosion resistance compared to the more general 304/316 stainless steel grades. This made them an excellent choice for […]

1.4507 is the DIN reference to a 25% chromium content super duplex stainless steel better known as Ferralium 255. The very first commercially produced super duplex stainless steel was Ferralium 255 which was developed by Langley Alloys. Launched in 1969, it has now provided more than 50 years of successful service in a wide range […]

S32550 and S32750 are both super duplex stainless steels, based around a 25% chromium alloying addition. S32550 is supplied with a higher yield strength than S32760 in solid bar form and has a 2% copper addition that provides superior resistance to sulphuric acid. Ferralium 255 was the very first commercially produced super duplex stainless steel. […]

S31803 and S32760 both share a duplex microstructure, which means they are produced with a balance of austenitic and ferritic grains. This means that duplex stainless steels combine physical and mechanical properties of both, making them an attractive and cost-effective proposition. However, S32760 is more highly alloyed than S31803, having a chromium content of 25% […]

S32750 and S32760 are both super duplex stainless steels, with a great deal of similarities and can often be substituted for the other, subject to customer specifications. The internal microstructure of these grades is a balance of austenitic and ferritic grains, which give a favourable combination of physical and mechanical properties. This mixed microstructure is […]

32760 is a super duplex stainless steel, based upon chromium additions of 25% to achieve excellent corrosion resistance. 32760 is shorthand for the grade identified as UNS S32760 by the unified numbering system. The grade now referred to as 32760 has its roots in a development in the 1980’s by Mather & Platt and subsequently […]

Super duplex stainless steels are grades that have a combination of austenitic and ferritic microstructures, based upon a chromium content of 25%. There have been a large number of grades developed over the last 50 years that meet this basic classification. However, the most popular ones are described below. ASTM A182 F51 equates to UNS […]

‘Duplex’ stainless steels are a family of stainless steels that contain a mixed microstructure of austenite and ferrite phases. They offer a combination of good corrosion resistance and high strength, making them suitable for a wide range of applications. Within the family of ‘duplex’ stainless steels, there are numerous specific grades using different compositions to […]

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

Sigma phase is a chromium-rich intermetallic phase found in stainless steels, that forms when an alloy is cooled slowly.

SAF is an acronym of Sandvik Austenitic Ferritic and is a registered trademark of Sandvik Intellectual Property AB.