What is 1.4507? Super Duplex

1.4507 is the Werkstoff number for a super duplex stainless steel most commonly known as Ferralium 255. The Werstoff designation was developed by the German standards body DIN, with the term Werkstoff translating approximately to ‘material’.

Ferralium is the original super duplex stainless steel. It was developed by Langley Alloys throughout the 1960’s and a patent application submitted in 1967. At this time, Langley Alloys operated a foundry, forge, rolling mills, laboratory and valve manufacturing business. Therefore, trial alloys were to be utilised in Langley Alloys own products. When the patent was formally granted in 1969, the developmental ‘Langalloy 40R’ product was re-branded as Ferralium.

Super duplex stainless steels possess a combined austenitic and ferritic microstructure which provides them with an optimum set of physical and mechanical properties. They achieve high strength, excellent resistance to corrosion and stress corrosion cracking, and are very cost effective compared with more highly-alloyed alternatives.

Compared with other super duplex stainless steels, Ferralium 255 has the greatest yield strength (85ksi / 586N/mm2) which allows for thinner sections to be used for the same functional performance. The use of 2% copper addition in Ferralium 255 provides superior resistance to sulphuric, nitric and phosphoric acid, whilst the high chromium level ensures long-term performance in seawater.

Langley Alloys stocks Ferralium 255 (1.4507, F61, X2CrniMoCuN, UNS S32550) as solid bars between 1/2” (12.7mm) and 14” (355.6mm) diameter. Our stock is certified to NACE MR0175 / ISO 15156-3, and produced in a Norsok-qualified mill.

Got any Questions? Get in Touch

For more information about our range of duplex stainless steels, please don’t hesitate to contact us today. We would be happy to answer any questions that you may have regarding specifications and common applications.