There only two essential constituents in conventional chromium plating bath; chromic acid and one or more catalyst acid radicals or anions. Chromium metal will not serve satisfactory as anode, owing two high solubility, insoluble anodes are used on chromium electroplating process, generally are lead.
Chromium metal is also appreciably more expensive. The chromium to be deposited is introduced into the bath as chromium trioxide, CrO3- (Chromic anhydride), commonly called chromic acid. It is reddish brown, hygroscopic material, easily soluble in water to give solution containing mainly H2Cr2O7. Many manufacturers, now aware of the effect of even small amount of catalyst acid radicals, furnish a pure grade of chromic acid especially suited for chromium plating. The chromic acid is made to meet specification which require that it contain not more than a small of percent of sulfate and be free from other catalyst such as chloride.
More detail see on Bath Function of Chromium Electroplating and type of metallic coating like chrome plating, bright chrome plating, dull black chrome plating, white chrome plating, gold color chrome plating, silver plating, gold plating, copper plating, anodizing, aluminum anodizing, black anodized, red anodized, yellow anodized, bronze color anodized, silver anodized, gold anodized, zinc coating, galvanizing.
Chromium metal is also appreciably more expensive. The chromium to be deposited is introduced into the bath as chromium trioxide, CrO3- (Chromic anhydride), commonly called chromic acid. It is reddish brown, hygroscopic material, easily soluble in water to give solution containing mainly H2Cr2O7. Many manufacturers, now aware of the effect of even small amount of catalyst acid radicals, furnish a pure grade of chromic acid especially suited for chromium plating. The chromic acid is made to meet specification which require that it contain not more than a small of percent of sulfate and be free from other catalyst such as chloride.
More detail see on Bath Function of Chromium Electroplating and type of metallic coating like chrome plating, bright chrome plating, dull black chrome plating, white chrome plating, gold color chrome plating, silver plating, gold plating, copper plating, anodizing, aluminum anodizing, black anodized, red anodized, yellow anodized, bronze color anodized, silver anodized, gold anodized, zinc coating, galvanizing.