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N. Rybakova, M. Souto, Y. Andriyko, W. Artner, J Godinho, G Nauer:
"Morphology and Mechanical Properties of TiB2 Coatings Deposited from Chloride-Fluoride Melts by Pulse Electroplating";
Journal of the Electrochemical Society, 156 (2009), 4; D131 - D137.

Electrodeposition of TiB2 coatings in molten chloride-fluoride electrolyte NaCl-KCl-NaF-K2TiF6-KBF4 at 700°C was investigated.
PP techniques in forms of periodically reversed PRC and periodically interrupted current PIC were applied, instead of
traditional dc procedure, which was also used for comparison, for the efficient deposition of the coatings onto molybdenum,
stainless steel, and tungsten carbide substrates with different geometries and surface areas. The effect of current density, frequency,
and pulse shape on the coatings properties was studied. It was found that the morphology and roughness of the deposit depend
strongly on the deposition method and conditions. The coating with the lowest roughness Ra = 102 5 nm was obtained by
PRC PP. The values of microhardness were in the range of 1800-2400 MPa, depending on the pulse frequency in PIC electrolysis.
The residual stresses are related to the frequency of deposition and vary in the range of −0.7 to − 1.3 GPa, being the minimum
at pulse frequency of 20 and 100 Hz. It was also found that the TiB2 coating decreases wetting of the steel surfaces by molten
glass, which is of practical importance for tools working in these media.

contact angle electrolytes electroplated coatings electroplating microhardness surface morphology titanium compounds

http://dx.doi.org/10.1149/1.3060508