What are the indicators a part should have been HFIC cleaned prior to repair?
A. First, consider the material. If it is of high Nickel content, it probably will need HFIC cleaning. Second if a repair is accomplished by welding and the weld continues to crack or if repaired by brazing and the braze seems not to have penetrated below the surface, chances are good that the oxides formed during operation are still present and not allowing the repair to be complete.
