347 stainless steel is a columbium/tantalum stabilized austenitic stainless steel. Similar to 321 stainless, it has good intergranular-corrosion resistance compared to typical 18-8 type alloys. With the addition of columbium and tantalum, which have a stronger affinity for carbon than chromium, the carbides will tend to randomly precipitate at the grain boundaries rather than form continuous patterns.

Applications: 347 stainless steel is widely used in aircraft exhaust, collector rings, expansion joints and in high temperature chemical processing

347 is resistant to atmospheric conditions and should be considered for applications requiring intermittent heating between the temperatures of 800f (427c) and 1650f (899c)