Influência das condições de eletrodeposição sobre a resistência a corrosão, susceptibilidade à fragilização por hidrogênio e à corrosão sob tensão do aço ABNT – 4340 revestido com liga Zn/Ni
Ano de defesa: | 2011 |
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Autor(a) principal: | |
Orientador(a): | |
Banca de defesa: | |
Tipo de documento: | Tese |
Tipo de acesso: | Acesso aberto |
Idioma: | por |
Instituição de defesa: |
Universidade Federal de São Carlos
Câmpus São Carlos |
Programa de Pós-Graduação: |
Programa de Pós-Graduação em Ciência e Engenharia de Materiais - PPGCEM
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Departamento: |
Não Informado pela instituição
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País: |
Não Informado pela instituição
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Palavras-chave em Português: | |
Área do conhecimento CNPq: | |
Link de acesso: | https://repositorio.ufscar.br/handle/20.500.14289/7433 |
Resumo: | Zinc-nickel alloys were electrodeposited on ABNT 4340 high strength steel in chloride acid media. The effect of the electrolyte composition and electroplating conditions on cathodic efficiency, chemical composition, morphology and phase structure of the deposits was evaluated regarding their influence on the corrosion resistance of the coatings, resistance to corrosion fatigue cracking, susceptibility to stress corrosion cracking and hydrogen embrittlement of the coated part. The electrolyte composition, temperature and cathodic current density had influenced in a significantly manner the nickel content, phases structure, morphology and corrosion resistance of the coatings. In general, the amount of nickel and the fraction of phase in the alloys were promoted by decrease of current density, increase of temperature and nickel concentration in bath. The increase of the fraction, as well as the increase of the nickel content on monophasic alloys shifts the corrosion potential to more positive values and decreases corrosion current of the coatings. The results obtained allows to improve the knowledge about the relations between processing, structure and properties of electroplated Zn-Ni alloys in order to use these coatings on low alloy high strength steels components. |