| 摘要 |
In a process of phosphating metal surfaces of galvanized steel or of galvanized steel and aluminum, before a painting, the metallic surfaces are treated at a temperature between 40 and 60.degree.C with an aqueous phosphating solutions which contain 0.4 to 5.0 g/l Mg, 0.05 to 2.0 g/l Ni, 8 to 20 g/l P2O5 and at least one oxidizing agent and wherein the ratio of free acid to total acid is (0.02 to 0.15) : 1. Where aluminum is absent the metallic surfaces are treated with phosphating solutions which when used in a spraying process are adjusted to contain between 0.4 and 1.0 g/l zinc and when used in a spraying-dipping process and in a dipping process are adjusted to contain between 0.9 and 1.5 g/l zinc. In the presence of aluminum the metallic surfaces are treated with phosphating solutions which for use in a spraying process are adjusted to contain between more than 0.8 and 1.0 g/l zinc and for use in a spraying-dipping process or in a dipping process are adjusted to contain between 1.4 and 2.0 g/l zinc and further are adjusted to contain 80 to 400 mg/l fluoride (F(el) as determined with a fluoride-sensitive electrode immersed into the bath solution.
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