Austenitic stainless steel for high temperature environments.
Grades 321 and 347 are the basic austenitic 18/8 steel (Grade 304) stabilized by Titanium (321) or Niobium.
Combining high strength, resistance to scaling and phase stability with resistance to subsequent aqueous corrosion, 321 is suitable for applications in the temperature range of up to 1650°F [900°C]. As other austenitic grades, 321 have excellent forming and welding characteristics, are readily brake or roll formed and have outstanding welding characteristics. Post-weld annealing is not required.
The variant grade 321H is a modification of 321 with a higher carbon content, to provide improved high temperature strength.