Coating deposition on material surfaces improves properties of the material such as the chemical and tribological properties. The durability of the material can be maximized and the wearing away of the surface can be minimized either by increasing the hardness of the surface or by reducing adhesion on the surface of the material submitted to wear. At the present time, cutting tools are coated with TiN, TiCN and (TiAl)N, using physical vapor deposition, PVD, in order to increase their useful life. These coatings are characterized by high degree of hardness, excellent adherence, low porosity, and a high chemical and thermal stability. The cutting tools are submitted to degradation processes of oxidation and corrosion. In these processes, the surface roughness plays an important role. This work objectifies the development of a methodology to apply a three-dimensional topographical analysis to the study of oxidation on coatings and surfaces. In this work, the oxidation of (TiAl)N coatings on widea substrate subjected to temperatures ranging from 650 ºC to 800 ºC was studied, for oxidation times up to 120 minutes. The samples were analyzed by profilometry before and after the oxidation. The principal result of this work was the development of a methodology of three-dimensional topographical analysis, which can be applied to study of the surface process of materials. The more rigorous characterization of the surface topography, using several parameters beyond the usual roughness measurements, is important to elucidate the operating mechanisms in the processes of oxidation and corrosion of the materials.
Topographical analysis; oxidation; coatings
