Posted By John Lewis Hi everybody I have a question for all you people in the metal industries. Many processes require some kind of passivation of the metal being used to get rid of iron on the surface and prevent further corrosion. This is generally done with Nitric Acid or Hydrofluoric Acid, both pretty nasty materials. The metals we passivate are generally Cobalt Chrome, Titanium and Stainless steel, all aviation grades. There is now a move in some areas (led it seems by the Americans) to use a Citric Acid based material which is far better from an Environmental and H&S point of view. I would like to know if anyone has any experiences of this material and any problems that have arisen in either safety or production with its use. Any info' would be gratefully received. John