AQUEOUS SOLUTION AND METHOD FOR PHOSPHATIZING METALLIC SURFACES

摘要

The invention relates to an aqueous solution containing phosphate for producing phosphate layers on metallic surfaces made of iron, steel, zinc, zinc alloys, aluminum or aluminum alloys. Said solution contains 0.3 to 5 g Zn2+ /1, 0.1 to 2 g nitroguanidine/1 and 0.05 to 0.5 g hydroxylamine/1, whereby the S-value is between 0.03 and 0.3, and the ratio of the weight of Zn2+ to P2O5 = 1:5 to 1:30. The invention also relates to a phosphatizing method in which the metallic surfaces are cleaned, then treated with said aqueous solution containing phosphate for a period of 5 seconds to 10 minutes at a temperature ranging from 15 to 70 ~C, and finally, are rinsed with water.