CHROMATING PROCESS OR PHOSPHATE-CHROMATING PROCESS AND MATERIALS SUITABLE FOR IDENTIFYING THE TREATMENT PROCESS

摘要

Various additives are used to differentiate chemically among treatment baths as well as the chemically reacted coatings. The differentiation is done by adding to the standard chromating or phosphate-chromating baths one or more of the following metals in the form of oxides, acids or their salts: titanium, vanadium, manganese, cobalt, nickel, silver, hafnium, tungsten. The identification of the treatment process that has produced a certain workpiece is done preferably by means of non-destructive testing (surface analysis, microanalysis) of the treated workpieces.