ZERON® 100

ZERON 100 High Pressure Piping in a Reverse Osmosis Desalination Plant

ZERON® 100 (F55 Duplex / 25Cr Duplex) is a super duplex stainless steel for use in aggressive environments.

Its properties include:

    • Resistant to pitting and crevice corrosion in warm seawater with a guaranteed corrosion performance (PREN > 40)
    • Lower more stable price compared to nickel based alloys
    • Excellent resistance to stress corrosion cracking in both chloride and sour environments
    • Superior resistance to sulfuric acid at most concentrations
    • Improved resistance over austenitic stainless to erosion corrosion and corrosion fatigue
    • High Strength (80,000 psi minimum Yield Strength) permitting designs to reduce weight versus other corrosion resistant alloys
    • Readily weldable using ZERON 100 filler metal

ZERON 100 Fire Protection Piping on an offshore oil platform

ZERON 100 complies with UNS S32760, however, Rolled Alloys tightly controls the chemistry and production of ZERON 100 in strict accordance with the requirements of our in-house 'MDS' specifications which are tighter than standard ASTM specifications. This ensures a consistent quality product is produced with optimal corrosion resistance and charpy impact toughness.

Performance Profile

ZERON 100 was developed as a seawater resistant material for pump applications in the North Sea as a cast material. Its excellent performance, led to demand for the alloy in a wider range of product forms and the development of wrought product forms. The corrosion resistance and strength properties of ZERON 100 have led to its widespread adoption in a range of industries. Oil and gas applications include process, seawater, firewater and subsea pipework systems, with associated risers, manifolds, pressure vessels, valves and heat exchangers. Applications of ZERON® 100 (UNS S32760) in other industries include pollution control equipment such as flue gas desulfurization equipment (FGD), pulp and paper, power generation, chemical, pharmaceutical, desalination, mining, metallurgical and marine industries.

Optimized versions of ZERON 100 are available for specific applications. These include:

  • ZERON 100 FG (fastener grade) which is a strain hardened bar product available up to 2-1/2 inch diameter for high strength fasteners. ZERON® 100 FG is made to ASTM A276 condition S and also meets the tensile properties for  ASTM A193 grade B7.  It meets charpy impact toughness of 40 Joules (29.5 ft.lbf.) minimum at -50°C (-58°F).
  • ZERON 100X overalloyed weld filler for welding of ZERON 100 to itself and other stainless steels.
  • ZERON 100M matching weld filler for welding ZERON 100 components that will be post weld annealed.
  • ZERON 100HS (high strength) wire for slick line applications in oil and gas.


ZERON® 100 Concentric Reducers, ZERON® 100 Fittings, ZERON® 100 Flanges, ZERON® 100 Pipe, ZERON® 100 Plate, ZERON® 100 Round Bar, ZERON® 100 Sheet, ZERON® 100 Weld Wire

Common Trade Names

Super Duplex Stainless, UNS S32760, F55 Duplex, EN 1.4501, 25Cr Duplex, Super Duplex


  • Desal - Arona
  • Cantarell
  • Murrim Vessel
  • Sparge Pipes
  • Damper