ANODIC PROCESSES DURING ELECTRODEPOSITION OF NICKEL, ITS ALLOYS AND COMPOSITE COATINGS

The results of investigations of the anodic processes of electrodeposition of nickel, nickel-boron alloy, composite coatings nickel-ultrafine diamond and nickel-cobalt-aluminum oxide are presented. It was shown that the oxidation of the boron-containing additive occurs at potentials much more positive than the oxidation potential of nickel, which means that oxidation of the boron compound is impossible under real conditions of electrodeposition. During the electrodeposition of CEC, the anode process proceeds without any complications and the dissolution of the anodes occurs in the same way as in nickel-plating electrolytes, and the composite additives of UDD and Al2O3 do not affect the anodic processes.

ULTRA-DISPERSED ADDITIVES IN THE NICKEL COLLOID-ELECTROLYTE BATHS

The article presents the results of investigates of the effect of ultrafine additives - zirconium diboride, silicon carbide, diamond on the physic-mechanical properties of composite electrochemical nickel coatings obtained from colloid-electrolyte baths. It is shown that precipitation containing ultrafine diamond possess optimal values of microhardness, wear resistance and internal stresses. These coatings can be used as an alternative to chrome coatings on parts of agricultural machinery.

The effect of nano-additives on the processes of electrodeposition of nickel precipitation

The article presents the results of investigates of the effect of ultrafine additives (zirconium diboride, silicon carbide, diamond) on the physical and mechanical properties of composite electrochemical nickel deposits obtained from colloid-electrolyte baths. It was revealed that the most effective nanostructured additives are zirconium diboride and ultrafine diamond. Current efficiency and potentiostatic researches shew mutual participation of finely dispersed nickel hydroxide compounds in the formation of a composite electrochemical deposits and dispersed phase of zirconium diboride or ultrafine diamond that are attendant in the solution or formed during electrolysis and introduced into the electrolyte. It is shown that the optimal values of internal tensions and microhardness are associated with the hardening of the nickel matrix together with various nano-dispersed additives that are included in the deposit. These deposits can be used as an alternative to chrome deposits on parts of machinery.