Basic knowledge of duplex stainless steel

It combines the high toughness and weldability of austenitic stainless steel with the high strength and chloride stress corrosion resistance of ferritic stainless steel, and has advantages such as nickel saving and pitting corrosion resistance

What are the core performance advantages
Mechanical properties: The yield strength is significantly higher than that of austenitic stainless steel (about twice), while maintaining good ductility (elongation ≥ 25%). ‌‌

 

Corrosion resistance: In chloride containing ion media (such as seawater), the resistance to pitting and crevice corrosion is superior to that of ordinary austenitic stainless steel (such as 316L). Outstanding resistance to stress corrosion cracking, especially in chloride environments above 60 ° C. ‌‌
Economy: With lower nickel content, the cost is better than high nickel austenitic stainless steel. ‌‌

 

What is the difference between duplex stainless steel and 316 stainless steel?
A significant difference between duplex stainless steel and 316 stainless steel is the corrosion resistance of each alloy. Although 316 is one of the most corrosion-resistant products in the 300 series, duplex stainless steel has much higher resistance to corrosive pitting when chloride is present

 

What are the common grades of duplex stainless steel?
Including 2205 (S32205), 2304 (S32304), 2507 (S32750), etc.

 

What are the types of duplex stainless steel?
Low alloy type, medium alloy type, high alloy type, and super duplex stainless steel type.