Bath Nitriding

Nitriding in a hot salt bath gives the part a thin, hard surface layer that provides good wear resistance. If you need to weld afterwards, that's critical because the layer breaks up during welding and you get problems with porosity or cracks. The layer must be removed beforehand, ideally by grinding or pickling, otherwise you won't get a clean weld. And the bath itself is nothing to play with; the part must be clean and dry before dipping, otherwise it spatters.