Why do stainless steel weld joints have to be prepared for welding?
The tightly adherent oxide associated with stainless steel has a higher melting point than the base metal. This would require higher heat imputs than desired or recommended to melt these oxides. Consequently, oxides should be removed from the adjacent surfaces to the weld, before welding, to ensure sound welds without oxide being taken into the weld pool and resulting in oxide inclusions.
