EVARISTO, B. O.; http://lattes.cnpq.br/9825647987597365; EVARISTO, Bianca de Oliveira.
Abstract:
This work presents a study of a metallic coating of the Zn-Ni-P alloy obtained on an API 5L
X65 steel substrate and its main characterizations regarding chemical composition, crystalline
and grain structure and resistance to corrosion. Zn-Ni-P alloy is a current proposal for
comparison with the protection methodologies currently used in the petroleum, aeronautics and
even automotive industries that often present toxic chemical elements in their composition, such
as Cadmium. The interest in the comparison arises from the understanding that corrosion
protection techniques are in constant evolution and study to offer the lowest possible risk in the
accomplishment of the tasks, be it human or environmental risk. Zn-Ni alloys are known to
provide a cathodic type protection to ferrous substrates, increasing the interest of evaluating the
behavior of the corrosion resistance of the substrate + coating set in an environment that
simulates the corrosive action. The coatings studied were obtained from the electrodeposition
technique with variation of current density and temperature, in a range of 34 to 76 mA / cm²
and 38 to 64ºC, respectively. The coatings were characterized regarding the structure and
morphology of the deposit on the steel surface. Analysis of the structure showed a uniform
crystalline structure, in most of the experiments, and the appearance of oxides. The study of the
morphology revealed the presence of small and compacted nodules for the best result of
resistance to corrosion. As for the evaluation of the corrosion resistance, the coatings were
submitted to a corrosive medium, a solution of NaCl (3.5%) simulating the sea water. For the
best result a resistance of 6,119γ kΩ and corrosion current of β7,β81 μA was obtained.
