WAGNER IZALTINO ALVES DOS SANTOS
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Artigo IPEN-doc 21246 Investigação de tratamentos alternativos à cromatização aplicados sobre eletrogalvanizado2012 - FERREIRA JUNIOR, J.M.; TOMACHUK, C.R.; OLIVEIRA, M. de; SANTOS, W.I.A.; COSTA, I.A cromatização com íons de cromo hexavalente tem sido utilizada como processo altamente efetivo de inibição da corrosão de revestimentos de zinco. Todavia, como apresenta efeitos tóxicos e carcinogênicos e envolva altos custos no tratamento de efluentes, muitas pesquisas têm sido realizadas com o objetivo de encontrar alternativas para este processo. Neste trabalho, foram investigados três tratamentos de conversão , sobre revestimento de zinco eletrodepositado que consistiram de: (a) passivação com íons de cromo trivalente e cobalto; (b) passivação com íons de cromo trivalente e zircônio e; (c) passivação com íons de cromo hexavalente, este úlitmo como referência. A resistência à corrosão das superfícies com os vários tratamentos foi avaliada por espectroscopia de impedância eletroquímica e ensaio de névoa salina segundo norma ASTM B117. Os resultados mostraram que a proteção contra a corrosão proporcionada pela camada de cromato trivalente e cobalto foi superior à das demais camadas, podendo substituir o tratamento de passivação à base de íons cromo hexavalente.Artigo IPEN-doc 22685 Hydrothermal surface treatments with Cerium and Glycol molecules on the AA 2024-T3 clad alloy2016 - SANTOS, WAGNER I.A. dos; COSTA, ISOLDA; TOMACHUK, CELIA R.New treatments for replacement of chromate require lower toxicity and corrosion protection. This study aims to investigate the influence of the combination of a Ce conversion coating (CCCe) with glycol molecules on the corrosion resistance of the AA2024-T3 clad (AA1230). The corrosion resistance of surface treated and untreated samples was evaluated by electrochemical techniques (electrochemical impedance spectroscopy, polarization tests and open circuit potential). These tests were complemented by salt spray tests to accelerate the corrosive effects of weathering. The surfaces were analyzed after corrosion tests by scanning electron microscopy with X-ray energy dispersive detector (SEM - EDX). The results of the CCCe samples in combination with glycol were compared with that of the surface with chromate layer and the results showed that the CCCe treatment is a candidate for replacement of chromating with the advantage that it does not generate toxic residues. The self-healing capacity of the new treatment tested was indicated by the increased formation of corrosion products deposition on top of Fe rich intermetallis in the AA1230 clad with time of exposure to the electrolyte.Artigo IPEN-doc 23663 Hydrothermal surface treatments with Cerium and Glycol molecules on the AA 2024-T3 clad alloy2016 - SANTOS, WAGNER I.A. dos; COSTA, ISOLDA; TOMACHUK, CELIA R.New treatments for replacement of chromate require lower toxicity and corrosion protection. This study aims to investigate the influence of the combination of a Ce conversion coating (CCCe) with glycol molecules on the corrosion resistance of the AA2024-T3 clad (AA1230). The corrosion resistance of surface treated and untreated samples was evaluated by electrochemical techniques (electrochemical impedance spectroscopy, polarization tests and open circuit potential). These tests were complemented by salt spray tests to accelerate the corrosive effects of weathering. The surfaces were analyzed after corrosion tests by scanning electron microscopy with X-ray energy dispersive detector (SEM - EDX). The results of the CCCe samples in combination with glycol were compared with that of the surface with chromate layer and the results showed that the CCCe treatment is a candidate for replacement of chromating with the advantage that it does not generate toxic residues. The self-healing capacity of the new treatment tested was indicated by the increased formation of corrosion products deposition on top of Fe rich intermetallis in the AA1230 clad with time of exposure to the electrolyte.Artigo IPEN-doc 18976 Potencialidade das camadas de conversão de cério (CCCe) na substituição do cromato sobre a liga AA 2024-T3 clad2012 - IZALTINO, W.A.S.; OLIVEIRA, M.; COSTA, I.Artigo IPEN-doc 20014 Bronze as alternative for replacement of nickel in intermediate layers underneath gold coatings2013 - SANTOS, WILMA A.T. dos; SANTOS, WAGNER I.A. dos; ASSIS, SERGIO L. de; TERADA, MAYSA; COSTA, ISOLDA