Fluoride zinc-cadmium based

TELLURIUM (13494-80-9) Finely divided powder or dust may be flammable and explosive. Violent reaction with strong oxidizers, bromine pentafluoride, halogens, interhalogens, iodine pentafluoride, hexalithium disilicide, lithium silicide, nitrosyl fluoride, oxygen difluoride, sodium peroxide, sulfur, zinc. Incompatible with cadmium, cesium, hafnium, strong bases, chemically active metals, iodic acid, iodine oxide, lead chlorite, lead oxide, mercury oxides, nitric acid, peroxyformic acid, platinum, silver bromate/iodate/ fluoride, nitryl fluoride, sodium nitrate. 

Conversion coating processes produce a thin film of predominantly chromium oxide on metal surfaces. The colour of this film depends on the substrate metal, and may vary in colour, from pale-yellow to gold to dark-brown or black. Today, the most commonly used CCC process for aluminium, zinc and cadmium (Biestek and Weber 1976) is an acid treatment (pH 1—2), based on a two-part solution containing a source of hexavalent chromium ion, e.g. chromate, dichromate or chromic acid. The solution for treating aluminium alloys, generally contains fluoride ion, which assists in the dissolution of the original oxide film, and an accelerator, e.g. ferricyanide, to facilitate the formation of the chromium oxide (Biestek and Weber 1976). 

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