Can different grades of stainless steel be welded to one another?
For purposes of welding, most grades of stainless steel within the same family (i.e. 300 series to 300 series) are compatible. Welding different families of stainless steel (i.e. 300 series to 400 series) is more problematic. It is important when welding together different grades of stainless steel to ensure that each of the grades is adequately suited for the application. When welding stainless steel a filler rod or electrode made of stainless steel must be used.