Russian Journal of Applied Chemistry, 2011, Vol. 84, No. 10, pp. 1732−1737.
Pleiades Publishing, Ltd., 2011.
Original Russian Text © V.I. Balakai, N.Yu. Kurnakova, K.V. Murzenko, I.F. Byrylov, D.N. Kuznetsov, 2011, published in Zhurnal Prikladnoi Khimii, 2011,
Vol. 84, No. 10, pp. 1640−1645.
AND CORROSION PROTECTION OF METALS
Study of Properties of Lustrous Nickel Coatings Deposited
from a Low-Concentration Chloride Electrolyte
V. I. Balakai, N. Yu. Kurnakova, K. V. Murzenko, I. F. Byrylov,
and D. N. Kuznetsov
South-Russian State Technical University (Novocherkassk Polytechnic Institute, Novocherkassk,
Rostov-on-Don oblast, Russia
Received May 12, 2010
Abstract—Effect of electrolysis modes on the physicomechanical properties of lustrous nickel coatings deposited
from a low-concentration chloride electrolyte was examined. Results obtained in an experimental study of the
industrial use of the given electrolyte are presented.
Use of dilute electrolytes meets requirements of
environment protection because this can diminish
the content of heavy metal ions in wastewater and
atmosphere and even enable development of low-waste
and waste-free technologies. A considerable economical
effect can be achieved owing to a decrease in the reagent
consumption for preparation and adjustment of the
electrolyte and lower expenses and energy expenditure
for wastewater puriﬁ cation. In some cases, coatings
with new functional properties can be obtained.
Chloride nickel-plating electrolytes are advantageous
over sulfate and sulfate-chloride electrolytes in having
a higher electrical conductivity, causing no anode
passivation, and exhibiting a weaker tendency toward
coagulation of sols [1, 2].
It was shown in  that, in the course of electrolysis
in a chloride nickel-plating electrolyte, the near-cathode
layer is alkalized and colloidal and ﬁ nely dispersed
compounds of the metal being electrodeposited are
formed. It follows from  that particles of the hydroxide
being precipitated upon alkalization of the solution bear
a positive charge if a metal chloride is the starting salt,
and a negative charge if this is the metal sulfate.
The stability of colloidal and ﬁ nely dispersed
compounds and basic salts of nickel in the near-cathode
layer in the presence of nickel chloride may result in that
unreduced molecules of nickel compounds, contained in
a dispersed particle, are incorporated into a coating and
thereby lead to changes in coating properties [luster,
internal stress (IS), microhardness, adhesion, corrosion
resistance, uniformity of the deposit distribution over
article surfaces, and porosity].
The goal of our study was to examine properties
of nickel coatings deposited from a low-concentration
chloride electrolyte and the possibility of their use for
deposition of protective-decorative coatings.
We used an electrolyte of composition (electrolyte 1)
O 100, NiSO
O 5, H
chloramine B 1.5; still bottoms of 1,4-butynediol (SBB)
5 ml l
. The electrolysis mode was the following:
temperature 20–60°C, pH 1.0–5.0, cathode current
density 0.5–12 A dm
. Nickel was deposited onto
articles made of St.3 steel, M1 copper, and L63 brass
in a 250-ml cell. The sample surface was pretreated by
the known methods . NPA-1 nickel served as anodes.
The microhardness of coatings with thicknesses of no
less than 25 μm on a copper plate was determined with
PMT-3 microhardness meter at an indenter load of 50 g
in conformity with GOST (State Standard) 2999–75. The