PROCEDIMIENTO PARA FABRICAR UN ARTICULO METALICO QUE TIENE UN RECUBRIMIENTO POR CONVERSION QUIMICA SOBRE SUPERFICIES DE HIERRO Y-O DE ZINC DEL MISMO.

摘要

Aqueous compositions and low temperature processes for treating clean steel and galvanized steel to provide a coating suitable for the application of paint thereto. The aqueous treating compositions contain: -Ingredient Quantity -zinc ion from about 0.9 to about 2.5 g/l; -nickel ion from about 0.6 to about 2.0 g/l; -orthophosphoric acid from about 15 to about 45 g/l; -nitrate ion from about 1.0 to about 10.0 g/l. - The pH of the composition is adjusted to 3.0-3.5 by addition of alkali metal hydroxide. The above composition is used on clean galvanized steel. For clean ungalvanized steel, from about 0.10 to about 0.65 g/l of nitrite ion is included in the composition. Optional ingredients in the above compositions include chlorate ion, ferric ion, and a fluoride compound. The invention also relates to a metal activating composition comprising an aqueous colloidal solution of manganese ion and a titanium compound.