Stainless 309

Annealing Procedure

1900-2050 F (1038-1121 C), water quench.

Applications

Oven linings, boiler baffles, fire box sheets, furnace components and other high temperature containers.

Cold Workability

Although this alloy has a high work hardening rate, it can be drawn, headed, upset, and stamped. Full annealing is required after cold work to remove internal stress.

Hardening Procedure

This alloy does not respond to heat treatment. Cold work will cause an increase in both hardness and strength.

Hot Workability

Working temperatures are 2150 F (1177 C), with reheating necessary at 1800 F (982 C).Rapid quenching is recommended. Full post-work annealing is required to reattain maximum corrosion resistance.

Machinability

This alloy machines similarly to type 304 stainless. Its chips are stringy and it will work harden rapidly. It is necessary to keep the tool cutting at all times and use chip breakers.

Principle Design Features

This alloy is known for good strength and oxidation resistance in continuous service temperatures up to 2000 F (1093 C).It is superior to 304 stainless in both strength and corrosion resistance.

Weldability

Most of the austenitic stainless steels can be readily welded using fusion or resistance methods. Oxyacetylene welding is not recommended. Filler metal should be AWS E/ER 309 or 309L.