For Highly Corrosive Environments
Supra
The Supra range contains austenitic and ferritic stainless steels grades for medium to highly corrosive environments in PRE range 22 – 26.
The most widely used molybdenum alloyed austenitic stainless grade, Supra 316L/4404 (EN 1.4404) , defines the overall landscape of the Supra range. The Supra range is complemented by a modern stabilized molybdenum alloyed nickel-free 18% chromium ferritic stainless steel alternative, Supra 444/4521 (EN 1.4521).
The latest Supra range addition is the austenitic Supra 316plus/4420 (EN 1.4420). Thanks to higher chromium and nitrogen, Supra 316plus has higher corrosion resistance and strength compared to 316L.
Supra range Cr-Ni-Mo austenitic stainless steels have excellent corrosion resistance, welding and forming, especially stretch-forming characteristics. Austenitic steels exhibit very high ductility also down to cryogenic temperatures. Due to the higher toughness and work hardening nature of austenitic stainless steels, special attention may be needed during forming and machining compared to ferritic stainless or carbon steels.
Modern Supra range stabilized molybdenum alloyed ferritic stainless steel, Supra 444/4521, has excellent corrosion resistance, welding and deep-drawing properties. Nickel-free ferritic stainless steels grades have excellent resistances to chloride-induced stress-corrosion cracking. Ferritics have good heat transfer properties that can be utilized in applications where uniform and fast heat transfer is preferred. Good heat transfer with lower thermal expansion eases weldability via smaller weld distortion and buckling behavior than austenitics. In addition, ferritics have similar machinability as carbon streels, due to low work hardening characteristics.
Supra range grades can be used in a wide range of applications supported with a broad selection of surface finishes from mills and service centers.