321 stainless steel is most similar to 304 stainless steel, however it contains the addition of Titanium making it an excellent choice for prolonged high temperature applications. The addition of Titanium stabilizes this grade of stainless steel against the formation of Chromium Carbide in heat ranges between 800 to 1500 degrees Fahrenheit.

Applications
Aircraft exhaust stacks
Manifolds
Chemical processing equipment
Welded equipment
Jet engine parts