321  Stainless Steel

A Titanium Stabilized Austenitic Stainless Steel with Excellent Resistance to Intergranular Corrosion After Exposure to Temperatures in the Chromium Carbide Precipitation Range of 800–1500°F (427–816°C)

Alloy 321 (UNS S32100) is a titanium stabilized austenitic stainless steel with good general corrosion resistance. It has excellentresistance to intergranular corrosion after exposure to temperatures in the chromium carbide precipitation range of 800–1500°F (427–816°C). The alloy resists oxidation to 1500°F (816°C) and has higher creep and stress rupture properties than alloys 304 and 304L. It also possesses good low temperature toughness. Alloy 321H (UNS S32109) is the higher carbon (0.04–0.10) version of the alloy. It was developed for enhanced creep resistance and for higher strength at temperatures

above 1000°F (537°C). In most instances, the carbon content of the plate enables dual certification. Alloy 321 cannot be hardened byheat treatment, only by cold working. It can be easily welded and processed by standard shop fabrication practices.

Mechanical Properties

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

Cold Forming
The alloy is quite ductile and forms easily.

Welding
Alloy 321 can be readily welded by most standard processes. A post weld heat treatment is not necessary.