Alloy S31803 and Alloy S32205 Duplex Stainless Steel

Alloy S31803 and S32205 stainless steel is a dual-phase stainless steel whose grain structure is ferritic and austenitic, hence the name “duplex”. With twice the mechanical strength and corrosion resistance of common austenitics, alloy S31803 and S32205 stainless steel offers some advantages over 316L and 317L:

• Lower coefficient of thermal expansion and a higher thermal conductivity
• Resists chloride stress corrosion cracking
• Pitting and crevice corrosion resistance
• Excellent choice for high chloride environments
• Lower cost than high alloyed austenitic

Excellent general corrosion resistance; superior to Grade 316 steel in most environments. Excellent resistance to localized corrosion including inter granular, pitting and crevice corrosion; the CPT of 2205 is generally at least 35ºC. The grade is also resistant to chloride stress corrosion cracking (SCC) at temperatures of up to about 150ºC. Grade 2205 will often perform well in environments which cause premature failure of austenitic grades. It has better resistance to sea water than Grade 316.