SUS321 Stainless Steel: Titanium-Stabilized Features

SUS321 is a Japanese standard stainless steel that is equivalent to AISI 321 or UNS S32100 in American standards. It is a titanium stabilized austenitic stainless steel that features improved resistance to intergranular corrosion and high-temperature applications. In this blog post, we will introduce the chemical composition, mechanical properties, physical properties, processing method, characteristics, and applications of SUS321 stainless steel.

 

The chemical composition of SUS321 stainless steel is listed in the following table based on JIS G4303 standard.

Element	Weight %
C	≤ 0.08
Si	≤ 1.00
Mn	≤ 2.00
P	≤ 0.045
S	≤ 0.030
Cr	17.0-19.0
Ni	9.0-12.0
Ti	≥ 5× (C+N), ≤ 0.70

The addition of titanium stabilizes the carbon and prevents the formation of chromium carbide at the grain boundaries, which can cause intergranular corrosion when the steel is heated to a temperature within the sensitization range (such as during welding).