Type 321 is basic 18/8 steel stabilized by a titanium addition. It is not sensitive to intergranular corrosion when heated within the carbide precipitation range of 800-1600 degrees F and can be used in this temperature range in corrosive environments.

Corrosion Resistance: Excellent. Equivalent to Types 302 or 304 in the annealed condition...and superior if a weldment in these grades has not been post-weld annealed or if the application involves service in the 800-1600 degrees F range.

Heat Resistance: Good oxidation resistance in intermittent service to 1600 degrees F and in continuous service to 1700 degrees F. Performs as well as any of the heat resisting stainless steels in the 800-1600 degrees F range where serious corrosive conditions are present.

Heat Treatment: Annealing - Heat to 1750-2050 degrees F and cool rapidly for maximum corrosion resistance. Stabilizing - Heat to 1550-1650 degrees F for one hour per inch of thickness and air cool. Stess Relief - Heat to 1300 degrees F for one to two hours and air cool. This grade cannot be hardened by thermal treatment.

Welding: Good characteristics suited to all standard methods. Use Type 347 filler rod or electrodes.

Typical Applications
Aircraft exhaust manifolds
Expansion joints
Bellows
Furnace parts
Heating element tubing.