321 Stainless Steel
Type 321 Stainless Steel is covered by the following specifications:AMS 5510, ASTM A240.
Chemical Composition: ASTM A240
|Chromium||17.00 – 19.00|
|Nickel||9.00 – 12.00|
|Titanium||5x(C+N) min. – 0.70 max.|
|Type||Yield Strength 0.2% offset (KSI)||Tensile Strength (KSI)||% Elongation (2" Gauge length)||Hardness Rockwell|
|321||30 min.||75 min.||40 min.||HRB 95 max.|
Type 321 can be readily formed and drawn, however, higher pressures are required and more springback is encountered than for carbon steel and ferritic stainless steels. Like other austenitic stainless steels,Type 321 work hardens quickly and may require annealing after severe forming.The presence of certain alloying elements can make Type 321 more difficult to form than other austenitic grades such as 301, 304 and 305.
Type 321 is non-hardenable by heat treatment.Annealing: Heat to 1750 – 2050 °F (954 – 1121°C), then water quench or air cool.
The austenitic class of stainless steels is generally considered to be weldable by the common fusion and resistance techniques. Special consideration is required to avoid weld ”hot cracking” by assuring formation of ferrite in the weld deposit. This particular alloy is generally considered to have comparable weldability to Types 304 and 304L. A major difference is the titanium addition that reduces or prevents carbide precipitation during welding. When a weld filler is
needed, either AWS E/ER 347 or E/ER 321 is most often specified.Type 321 is well known in reference literature and more information can be obtained in this way.