Fluoride Ion Cleaning as a pre-braze process

Fluoride Ion Cleaning (FIC), synonymous with Hydrogen Fluoride (HF) cleaning is an extremely effective process for the removal of metallic oxides from metal alloys.  It was developed by a major jet engine manufacturer as a cost effective repair process for nickel based airfoil components.  Today it is widely used to prepare nickel and cobalt based supper alloys for braze repair / Activated Diffusion Healing (ADH) on jet engines and industrial gas turbines.

Conventional processes such as Hydrogen Cleaning were effective for a wide range of stainless steels, cobalt and nickel based alloys.  However hydrogen is not very effective on alloys containing significant amounts of aluminum and titanium.  These two metals severely oxidize to form complex spinels on hardware surfaces that penetrate deeply into existing cracks.  Only cleaning methods utilizing the fluoride-ion technique are currently capable of removing these deeply imbedded oxides.