Caracterização da rugosidade em superfícies nitretadas a plasma da liga Ti6Al4V

Abstract

This paper deals with the characterization of topographic changes occurred on surfaces of plasma nitrided Ti6Al4V-ELI alloy. Surface roughness is an important parameter of materials used in situations involving friction, attrition, corrosion and biocompatibility, as the case of orthopedic implants. It is known that rough surfaces exhibit characteristic patterns of light scattering, or distribution of intensity of brightness in images. Moreover, it is well established the fact that the roughness influences the differentiation and activity of bone cells in contact with the implant surface. To characterize the changes in topography, in the different conditions of nitriding of the samples, first we obtain images of the top acquired through the technique of scanning electron microscopy (SEM). With the application of fractal geometry, a study of the surface layers of titanium nitride formed on the samples was realized. This study consisted of applying fractal analysis, using analysis software to determine the fractal dimensions of surfaces on plasma nitrided for different temperature conditions. The analysis showed different values for the measurement of fractal dimension in different temperature conditions in the process of nitriding. However, based on these data, the fractal analysis of SEM images of the surface is a parameter that is not possible to differentiate two conditions for nitriding and through this study is not possible to understand the dynamics of the process of nitriding.