Comparação entre um revestimento obtido por aspersão térmica e um revestimento obtido por galvanização, utilizados contra a corrosão

Abstract

Among the coating processes of materials, the thermal spray process has been developed in the last decades several studies and related research has been conducted. The thermal spray may be applied in several fields such as, for example, the coating of metal pipes in the petroleum industry, in order to improve mechanical properties of a surface, in most cases increasing its resistance to several types of corrosion Supplies of stainless type stand out among the most commonly used for this type of coating, because they have a high resistance to corrosion. The thermal spray powder by the process flame (TS - Thermo Spray) is a process which utilizes powdered materials with pre-defined size distribution, promoting the union of the material out of the superheated spray is fused to the substrate surface by forming a coating layer. In this work were made coatings by thermal spray process called powder using two materials which is the Nb (Niobium) and Al (Aluminum) by its high resistance to corrosion and cheaper prices, these were sprayed against a steel substrate ABNT 1020 . We performed a comparison between the thermal spray coating and other conventional hot dip galvanizing by using the same substrate, aiming at corrosion resistance. The samples were also submitted to the Vickers microhardness tests, optical microscopy, accelerated corrosion and diffraction of X-ray, and the accelerated corrosion test the main target of this research.The results are satisfactory doing a excellent formation of a superficial protection, building a better corrosion resistance.