How was Ferralium developed? Super Duplex
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.
Ferralium super duplex stainless steel embraced the mixed austenitic : ferritic microstructure to achieve a combination of high strength and excellent corrosion performance. Key aspects of its development include the elevated nitrogen content, that helps increase pitting corrosion resistance, plus the higher copper content to slow down pitting corrosion should it occur. Both of these items help to give Ferralium superior corrosion resistance over similar alloys.