Multilayered and nanostructured coatings of Ti based alloys (oxides and nitrides) are elaborated and tested for increasing protective properties such as corrosion and wear resistances. A pin-on-disc tribometer was used to evaluate the wear resistance in Hank's solution against bovine bone. Corrosion behavior in Hank's solution was determined by potentiodynamic and electrochemical impedance spectroscopy techniques. Besides, the specimen surfaces were characterized by Atomic Force Microscopy (AFM), Scanning Electron Microscopy (SEM) and Energy Dispersive Spectroscopy (EDS) microanalyses. The results showed that optimal tribological properties were obtained in the case of coatings having TiN as top layer. The main wear mechanism was abrasive third body wear. In vitro corrosion tests at 37°C showed that the better corrosion resistance was obtained when TiN was the top layer. However all of them exhibited good tribological properties, good corrosion resistance and then may be promising options for biomedical applications.

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The aim of this work is to investigate the tribological behaviour of a continuous hot dip galvanizedsteel. This paper presents a fundamental study of the characteristics of zinc coating in terms ofmorphology, surface roughness and tribological behavior according to process parameters typical ofindustrial processes continuous galvanization. The morphology of the zinc coating was observed byscanning electron microscope (SEM), optical microscopy, and the mechanical properties of thecoating layers were determined by nanoindentation. The tribological tests were carried out on arotating ball-disk tribometer under loads of 1, 2, 3Nwith a sliding distance of 15, 30 and 50 m. Theresults showed a marked increase of the coefficient of friction with increasing applied load. Under thesame conditions, wear slightly increased due to the hardness of intermetallic phases. The resultspresented show that heating promotes the diffusion of iron in the zinc coating giving shape to a binaryalloy Fe-Zn whose characteristics depend on the parameters; moreover, it is proved that thetribological characteristics of the surface of the metal blank in terms of coefficient of friction dependon the temperature of the contact pressure.

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