Langley Alloys Ltd.
Ferralium 255-SD50
Langley's own super duplex, developed in the 1960s: strength above most CRAs, with chloride SCC resistance.
Ferralium 255 is a super duplex stainless steel in the Ferralium family. It was the first commercial grade of super duplex stainless steel. Developed by Langley Alloys in the 1960's, and subsequently refined, to meet the needs of the oil, gas and chemical industries, Ferralium 255 achieves higher strengths than most other stainless steel varieties and corrosion-resistant alloys. It is resistant to chloride SCC, as well as crevice corrosion and pitting.
https://www.langleyalloys.com/materials/super-duplex/ferralium-255/
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