2205 duplex stainless steel pipe (both ferritic and austenitic) is used extensively in applications that require good corrosion resistance and strength. The S31803 grade stainless steel has undergone a number of modifications resulting in UNS S32205, and was endorsed in the year 1996. This grade offers higher resistance to corrosion.
At temperatures above 300°C, the brittle micro-constituents of this grade undergo precipitation, and at temperatures below -50°C the micro-constituents undergo ductile-to-brittle transition; hence this grade of stainless steel is not suitable for use at these temperatures.
The properties that are mentioned in the below tables pertain to flat rolled products such as plates, sheets and coils of the ASTM A240 or A240M. These may not be uniform across other products such as bars and pipes.
Table 1 provides the compositional ranges for grade 2205 duplex stainless steel pipe.
Table 1 - Composition ranges for 2205 grade stainless steels
The typical mechanical properties of grade 2205 stainless steels are listed in the table below. Grade S31803 has similar mechanical properties to that of S32205.
Table 2 - Mechanical properties of 2205 duplex stainless steel pipe
(% in 50mm) min
Rockwell C (HR C)