31803 Duplex

S31803 / F51 is a duplex stainless steel based on a 22% chromium 5% nickel alloying system. Also known as 2205 this is the most widely used of the duplex grades and offers a combination of good strength and ductility and a very high marine corrosion resistance (better than grades such as 316).

It offers an excellent resistance to intergranular corrosion, pitting (PREN ≥35) and crevice corrosion combined with a high resistance to chloride stress corrosion cracking at temperatures up to ~150ºC. These attributes have enabled it to become a proven material for many offshore and marine components that have to operate in critical conditions.

Chemical Composition

Related Specifications

Key Features

• High strength levels

• Very good resistance to pitting & crevice corrosion

• High resistance to stress corrosion cracking, fatigue and erosion

• Excellent resistance to chloride stress corrosion cracking

• Good workability and weldability

Typical Physical Properties

Fabrication Properties

Typical Applications

S31803 / F51 stainless has been used for components in food processing, power generation, paper and pulp industry, chemical processing and for offshore and marine activities. Components include pipework, high strength fasteners, wellhead and subsea wellhead fittings, desalination plant, seawater cooled heat exchanger, chemical tanks, flue gas filters and acetic acid distillation components.

This technical information is given by John Hood & Co.without charge and the user shall employ such information at their own discretion and risk. For more detailed technical advice on temper selection, fabrication, joining, machining, physical and mechanical data please contact us as space does not permit the listing of every feature of the material.