SU865994A1 - Copper-plating electrolyte for aluminium and its alloys - Google Patents

Description

(54) ELECTROLYTE OF ALUMINUM AND ALKMINIUM ALLOYS

I

The invention relates to the deposition of electroplating, such as copper, and can be used in electrical engineering, instrument engineering and mechanical engineering.

A known electrolyte for the plating of aluminum and aluminum alloys, containing a salt of copper and acetic acid D}.

; The disadvantage of this electrolyte is the low adhesion of the resulting coating, and moreover, the precipitates are usually obtained by darkening.

The closest in technical essence and the achieved result is an electrolyte containing copper salt, such as copper sulphate, acetic acid and a reducing agent, for example, tin dichloride.

The disadvantage of this electrolyte is the low adhesion of the coatings. to the substrate, especially from aluminum alloys, as well as when the base is immersed in the electrolyte without a rod, its etching is observed.

The purpose of the invention is povsece e coating adhesion.

This goal is achieved by the fact that the electrolyte of copper and aluminum and aluminum alloys, containing copper salt, acid and reducing agent, for example, salt of divalent tin, additionally contains sodium sulphosalicylic, and as the salt of copper and acid, respectively, copper nitric acid and acetic acid with the following ratio components, g / l:

IS

Copper nitrate i 100-250 Acetic acid 10-20 Reducing agent 0.02-1 Sodium sulfosalicylic 20-50

20

As a reducing agent, the electrolyte may contain, in addition to tin ions, metal ions that have variable valence, for example, manganese, evinz, vanadium, mercury, palladium, mouse antimony, bismuth, indium, iron, etc. in lower valence and organic substances possessing reducing properties, such as hydrazine, ascorbic acid, amines, etc. The electrolyte metal ions may contain nitrate, acetic, sulfuric, and hydrochloric acid salts. Sodium sulfosalicylic; enhances the adhesion of the copper coating to alkali and its alloys due to the interaction with the surface of the metal to be coated with the formation of complex compounds before the start of copper deposition, and also depassives the anodes, which increases the anode current density. The proposed solution is practically passive in relation to the metal being crushed.

The adhesion of coatings obtained from the proposed electrolyte is much higher than that of the known, especially during the deposition of coatings on aluminum alloys.

Claims (1)

Invention Formula Electrolyte of copper and aluminum alloy containing salt copper, an acid and a reducing agent, for example, a salt of divalent tin, characterized in that, in order to increase the adhesion of the coatings, it additionally contains sodium sulfosapicilic, and as a salt of copper and acid, respectively copper, nitrate and acetic acid at 4 The electrolyte is prepared as follows. The required amount of copper nitrate is dissolved in water, the calculated amount of acetic acid, sodium sulfosalicylic acid and reducing agent are added. The reducing agent is added as an aqueous solution. Deposition is carried out at a current density of 1.0-10.0 A / dm and a temperature of 1550 s. The dispersing ability of the electrolyte is determined by the Field method in a rectangular cell with the distance between the electrodes. The value of the scattering method of justice is 77%. The amount of adhesion is determined by the method of rupture on the bursting marshne of spare parts. The test results are shown in the table. 5 the following ratio of components, g / l: Copper nitrate 100-250 Acetic acid 10-20 Reducing agent 0.02-1 Sulfosalicylic sodium 20-50 865994 6 Sources of information taken into account during the examination - 1. USSR Author's certificate 5 51541, cl. C 25 D 3/38, 1937. 2, Copyright Testimony of the USSR No. 252806, cl. C 25 O 3/38, 1966.