FIELD: nonferrous industry; radio industry; instrument engineering; aircraft industry; other industries; methods of passivation of the copper and the copper alloys.
SUBSTANCE: the invention is pertaining to the method of passivation of copper and the copper alloys and may be used for their anticorrosion protection in the radio industry, instrument engineering, the aircraft industry and the other fields of the national economy for production of the articles used in the different climatic conditions. The method includes degreasing of the coated surfaces, flushing in the hot running water, flushing in the cold running water. Also with the purpose to increase their corrosion resistance of the coated surfaces, they are dipped at the temperature of 20 ± 5°С in the solution containing the chromium anhydrate - 145-150 g/l, the sulfuric acid - 35-40 g/l, the mixture of the nitric acid and water in the ratio of 3:3 - 25-30 ml/l, sodium chloride -8-10 g/l and the distillated water -up to one liter, and keep the coated surfaces in it for 1.7-2.3 minutes, and then conduct their flushing in the cold running water, removal of the drip moisture and the thermal treatment at the temperature of 80-100°С within 3-15 minutes.
EFFECT: the invention ensures the increased corrosion resistance of the articles surfaces coated with the copper and the copper alloys.
3 ex
