Stainless 321

Annealing Procedure

1800-2000 F (928-1093 C), air cool. This procedure will result in maximum ductility. For maximum corrosion resistance, see the note on stabilizing anneal under corrosion.

Applications

Jet engine parts, furnace heat treated parts, expansion joints, turbo superchargers, oil refiners, exhaust manifolds and high temperature chemical production equipment.

Cold Workability

Although this material requires higher initial forces than 304 stainless, it is quite tough and ductile and can be readily stamped, blanked, spun and drawn.

Hardening Procedure

This alloy does not harden by heat treating. Elevated properties may only be obtained through cold reduction.

Hot Workability

Working temperatures of 2100-2300 F (1149-1260 C) are recommended for forging, upsetting and other hot work processes. Do not work this alloy at temperatures below 1700 F ( 927 C). Material must be water quenched or fully annealed after working to reattain maximum corrosion resistance.

Machinability

Slightly tougher than 304 stainless, this material will produce the same tough stringy chips. The use of slow speeds and constant positive feeds will minimize this alloy's tendency to work harden.

Principle Design Features

The key feature of 321 stainless is its resistance to intergranular corrosion. It employs titanium as a stabilizing element against chromium carbide formation. This alloy also exhibits strength characteristics superior to those of 304 stainless.

Weldability

321 may be welded by all commonly used fusion and resistance methods. Oxyacetylene welding is not recommended. When necessary, use AWS E/ER347 filler metal.