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The main objective of the present work was to determine the influence of laser treatment on corrosion resistance of coatings deposited on C45 carbon steel by the electro-spark deposition process. The studies were conducted using WC-Cu electrodes produced by the powder metallurgy route. The technology uses the phenomena of electrode material erosion and spark discharge between the electrodes, leading to the formation of a surface layer with characteristics different from those of the substrate. The use of these protective layers provides optimum resistance to corrosion. [ABSTRACT FROM AUTHOR]

Abstract: The paper described properties of electro-spark deposited coatings under influence of the laser treatment process. The properties were assessed by analyzing the coating microstructure, microhardness and corrosion resistance tests and tribological studies. The tests were conducted for Mo and Cu coatings (the anode) which were electro-spark deposited over the C45 steel substrate (the cathode) and melted with a laser beam. The coatings were deposited by means of an ELFA-541. The laser processing was performed with an Nd:YAG laser. The coatings after laser processing are still distinguished by very good performance properties, which make them suitable for use in sliding friction pairs. [Copyright &y& Elsevier]

Abstract: The work presented in this paper determines the influence of the laser treatment process on the properties of electrospark coatings. The properties after laser treatment were examined by microstructure analysis, microhardness, roughness and adhesion tests. The studies were conducted using WC–Co–Al2O3 electrodes produced by sintering nanostructural powders. The anti-wear coatings were first deposited by an EIL-8A apparatus on C45 carbon steel and then laser melted within various process parameters. In this case Nd:YAG laser (BLS 720 model) was applied. The electro-spark deposited coatings are very promising to improve abrasive wear resistance of tools and machine parts, which was indicated by tribological tests. [ABSTRACT FROM AUTHOR]

Influence of laser power on the corrosive resistance of WC–Cu electrospark deposition (ESD) coatings on the C45 carbon steel surface in acidic chloride solution was examined. Potentiodynamic polarization technique was used. Scanning electron microscope (SEM) was employed for the observation the surface of materials. The structure of coatings was dependent on the composition of electrospark electrodes. The WC25–Cu75 coating the largest corrosion resistance was showed. The laser treatment of 70 W laser power caused the homogenization of the structure, and the healing of microcracks and pores of ESD coatings. After laser irradiation a decrease of the microhardness of WC25–Cu75 coating was observed. The corrosion rate of sample for the laser treatment of WC25–Cu75 coating was approximately one-fifth that of coating without laser irradiation. [ABSTRACT FROM AUTHOR]