Resumo

ROMERO, Nathalie et al. Evaluation of superficial chemical treatment to improve the performance of thermal sprayed aluminium coatings. Rev. Téc. Ing. Univ. Zulia [online]. 2014, vol.37, n.3, pp.197-205. ISSN 0254-0770.

The objective of this research is to study the behaviour of thermal sprayed aluminium coatings after the application of superficial chemical treatments; for this purpose, 11 types of chemical solutions were applied on carbon steel probes (10 cm × 15 cm × 3 mm) which were previously thermal sprayed with aluminium coatings; and evaluated according to ISO 11474 in accelerated environment for 5 months. The test probes were evaluated monthly by visual inspection and photographic record, and withdrawn at 2, 4 and 5 months of exposure for their further analysis in laboratory. Corrosion rate and the behaviour of thermal sprayed coatings were evaluated using electrochemical techniques: Electrochemical Impedance Spectroscopy (EIS) and Anodic Potentiodynamic Polarization Curves (ASV). The treatments of sulphuric acid, oxalic and aloe vera increase the performance of thermal spayed aluminium coating; while commercial rust converter and tannin decrease its performance.

Palavras-chave : thermal sprayed coating; superficial chemical treatment; electrochemical techniques.