Influence of composition and structure of nickel-boron coatings on their protective and decorative properties
In the present work, the influence of the composition and structure of the Nickel-boron coating on its protective and decorative properties is studied. These coatings were obtained by introducing a polyhedral additive Na2В10Н10 into standard Nickel electrolytes. It is shown that the mode of electrolysis and concentration of boron-containing additives determine the content of boron in the alloy and the structure of the coating, and, consequently, its protective,decorative and functional properties. It is established that the introduction of boron additives in Nickel electrolytes allows to obtain both crystalline (up to 1.1 % boron) and amorphous (over 4.3 % boron) Nickel-boron coatings. As the amorphousness increases, the micro roughness of the coating decreases slightly and the degree of gloss increases, and with a boron content of more than 2 %, practically non-porous coatings can be obtained. However, boron-containing additive input Na2В10Н10 is not an effective leveling and brightening additives and to obtain a shiny aligned coatings requires the introduction of a standard strong bishopapostles. In addition, the introduction of boron into the coating leads to an increase in the magnitude of the internal tensile stresses, which increase with the thickness of the layer, but decrease with increasing current density.