Analysis of Nucleation Phenomena for Metallic Chromium Coatings Formed on Nanostructured Surfaces By of a Pulsed Laser
Authors: Espinoza Gálvez Armando , Torres-González Julieta , Antaño López René 
Published: February 2020

Obtain metallic chromium (Cr0) deposits by trivalent chromium in aqueous solution have some disadvantages respect to hexavalent chromium. The obtention of this coatings are not considered feasible to directly from a simple dissolution. The chromium III in aqueous solution presents an octahedral structure [Cr(H2O)6]+3[3], so the baths for the trivalent chrome require complex forming agents. It is also found that is difficult to obtain the same thickness with chromium III as using chromium VI, J. Mcdougall et al[4] report that it is difficult to obtain deposits greater than 2 µm from trivalent chromium, attributed to microstructural differences, causing the properties of the chromium coatings be diminished compared with the hexavalent chromium.

A form to controlled the phenomena associated with the nucleation of the trivalent chromium electrolytic deposits is nanostructuring the surface sustrate where the electrodeposit is formed. This can do by pulsed laser-induced phenomenon change microstructure of the bulk. Some authors have reported significant improvements using treatments earlier of coats by pulsed lasers (femtosecond) [5][6][7]. The optimized characteristics reported are: Better Adherence, friction coefficients lower, even the nucleation type can be epitaxial.

Therefore, in the present project proposes electrochemical characterization by polarization curves, electrochemical impedance spectroscopy and cyclic voltammetry for substrates of 1008 carbon steel polished and nanostructured by a pulsed laser with pulse ultra-fast. Also structural and morphologic by scanning electron microscopy, X-ray diffraction, etc., Chronoamperometry was used for analyzed the nucleation phenomena on substrates polished and nanostructured materials.

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