Avaliação de aspectos metrológicos da retificação sobre a qualidade superficial de liga de titânio

Abstract

Titanium alloys are materials that have wide applications in the aerospace industry, as well as in biomedical components, due to a unique combination of properties, such as low density, high mechanical and corrosion resistance and biocompatibility with the human body. However, these materials have low machinability, due to their high mechanical resistance, low thermal conductivity and chemical reactivity with ceramic materials, which make up the cutting tools. Particularly in the grinding of titanium alloys, it is essential that an effective analysis be developed of the effects that process cutting parameters can have on the surface quality of ground surfaces. Thereby, a metrological analysis of the surface finish is necessary in terms of dimensional and geometric tolerances, and requirements of engineering projects, to ensure functionality and interchangeability between machined components. The application of measurement uncertainty concepts is essential for a reliable and traceable analysis of measured results. From this perspective, the purpose of the project is to present the effects generated by two different radial depths of cut conditions (ae = 10 µm and ae = 30 µm) on the surface quality of samples of the Ti 6Al 4V alloy, ground with a carbide grinding wheel. silicon (SiC), in terms of average roughness (Ra), images of ground surfaces (SEM), dimensional deviations and flatness deviations. From the application of measurement uncertainty in the results achieved, it was possible to verify that the change in radial depth of cut value from a soft condition (ae = 10 µm) to a more severe condition (ae = 30 µm), generated an increase of 34, 62% in the surface roughness parameter Ra, which showed greater evidence of plastic deformation, in terms of material displacement. Dimensional deviations and flatness deviations increased by 164.10% and 143.48%, respectively, which highlighted the influence of radial depth of cut conditions in the workpiece, on the quality of the Ti-6Al-4V ground samples.