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S31803 is almost identical to S32205 in terms of both composition, physical and tensile properties. S32205 is achieved by producing S31803 with certain elements – chromium, nickel and molybdenum, controlled to the upper limit of their range. As these three elements account for the resistance to pitting corrosion S32205 has a slightly improved and more […]

Duplex stainless steels have many attractive properties, with their high strength and excellent corrosion resistance achieved in a cost-effective way. As such, they have become widely used in a wide variety of applications. However, there are instances where their characteristics are not best suited and other grades may have to be used. ‘Duplex’ stainless steels […]

A duplex stainless steel is named because it has a ‘duplex’ microstructure, meaning 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. Austenitic stainless steels generally provide excellent corrosion resistance, good mechanical properties over a wide range […]

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. UNS S32550 UNS S32550 equates to […]

1.4410 is shorthand for DIN 1.4410, a super duplex stainless steel also identified by the specifications UNS S32750 and ASTM A182 F53. This particular 25% Cr super duplex stainless steel was originally developed by Sandvik (now Alleima) during the 1990’s and marketed as SAF2507. ‘Duplex’ stainless steels are a family of stainless steels that contain […]

The hardness of S32750 can vary from product form to product form, and from batch to batch. For solid bars of S32750 supplied to the common specifications of ASTM A182, ASTM A276 and ASTM A479, the maximum hardness allowable is 310 HB (Brinell Harness). For wrought and cast super duplex stainless steels such as S32750, […]

UNS S32750 is a super duplex stainless steel, also referred to as ASTM A182 F53 and DIN 1.4410. This particular 25% Cr super duplex stainless steel was originally developed by Sandvik (now Alleima) during the 1990’s and marketed as SAF2507. With an increased chromium content compared with F51 it offers improved pitting corrosion resistance.  The […]

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% […]