Morphological, structural, microhardness and corrosion characterisations of electrodeposited Ni-Mo and Cr coatings

Detalhes bibliográficos
Autor(a) principal: Lima-Neto,Pedro de
Data de Publicação: 2010
Outros Autores: Correia,Adriana N., Vaz,Gustavo L., Casciano,Paulo N. S.
Tipo de documento: Artigo
Idioma: eng
Título da fonte: Journal of the Brazilian Chemical Society (Online)
Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532010001000024
Resumo: The corrosion resistance of electrodeposited Cr and Ni-Mo coatings and the influence of heat treatment on the crystallographic structure, morphology and microhardness properties were investigated here. The characterisations were carried out using scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDX) techniques. Corrosion tests were performed at room temperature in 10-1 mol dm-3 NaCl solutions and by potentiodynamic linear polarization technique.TheMo content in the layer and current efficiency increased with the molybdate ion concentration in the plating solution, while the surface morphology evolved from rough and homogeneous to cracked surface with the increase of the amount of Mo in the layer. The electrochemical corrosion tests showed that the Cr coatings have better corrosion resistance than the Ni-Mo coatings in chloride medium and that all the studied coatings corrode in chloride medium. Ni-13Mo coating has the nobler corrosion behavior among the studied Ni-Mo coatings. The microhardness of the Ni-13Mo coatings increased as the annealing temperature increased which is related with the precipitation of Ni, Ni4Mo and NiMo phases during the heat treatment of this coating. Ni-13Mo coating is a potential substitute for chromium coating in industrial applications when operating at temperatures higher than 100 ºC and good microhardness properties are required.
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spelling Morphological, structural, microhardness and corrosion characterisations of electrodeposited Ni-Mo and Cr coatingsNi-MoCrelectrodepositioncorrosionheat treatmentmicrohardnessThe corrosion resistance of electrodeposited Cr and Ni-Mo coatings and the influence of heat treatment on the crystallographic structure, morphology and microhardness properties were investigated here. The characterisations were carried out using scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDX) techniques. Corrosion tests were performed at room temperature in 10-1 mol dm-3 NaCl solutions and by potentiodynamic linear polarization technique.TheMo content in the layer and current efficiency increased with the molybdate ion concentration in the plating solution, while the surface morphology evolved from rough and homogeneous to cracked surface with the increase of the amount of Mo in the layer. The electrochemical corrosion tests showed that the Cr coatings have better corrosion resistance than the Ni-Mo coatings in chloride medium and that all the studied coatings corrode in chloride medium. Ni-13Mo coating has the nobler corrosion behavior among the studied Ni-Mo coatings. The microhardness of the Ni-13Mo coatings increased as the annealing temperature increased which is related with the precipitation of Ni, Ni4Mo and NiMo phases during the heat treatment of this coating. Ni-13Mo coating is a potential substitute for chromium coating in industrial applications when operating at temperatures higher than 100 ºC and good microhardness properties are required.Sociedade Brasileira de Química2010-01-01info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersiontext/htmlhttp://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532010001000024Journal of the Brazilian Chemical Society v.21 n.10 2010reponame:Journal of the Brazilian Chemical Society (Online)instname:Sociedade Brasileira de Química (SBQ)instacron:SBQ10.1590/S0103-50532010001000024info:eu-repo/semantics/openAccessLima-Neto,Pedro deCorreia,Adriana N.Vaz,Gustavo L.Casciano,Paulo N. S.eng2010-12-01T00:00:00Zoai:scielo:S0103-50532010001000024Revistahttp://jbcs.sbq.org.brONGhttps://old.scielo.br/oai/scielo-oai.php||office@jbcs.sbq.org.br1678-47900103-5053opendoar:2010-12-01T00:00Journal of the Brazilian Chemical Society (Online) - Sociedade Brasileira de Química (SBQ)false
dc.title.none.fl_str_mv Morphological, structural, microhardness and corrosion characterisations of electrodeposited Ni-Mo and Cr coatings
title Morphological, structural, microhardness and corrosion characterisations of electrodeposited Ni-Mo and Cr coatings
spellingShingle Morphological, structural, microhardness and corrosion characterisations of electrodeposited Ni-Mo and Cr coatings
Lima-Neto,Pedro de
Ni-Mo
Cr
electrodeposition
corrosion
heat treatment
microhardness
title_short Morphological, structural, microhardness and corrosion characterisations of electrodeposited Ni-Mo and Cr coatings
title_full Morphological, structural, microhardness and corrosion characterisations of electrodeposited Ni-Mo and Cr coatings
title_fullStr Morphological, structural, microhardness and corrosion characterisations of electrodeposited Ni-Mo and Cr coatings
title_full_unstemmed Morphological, structural, microhardness and corrosion characterisations of electrodeposited Ni-Mo and Cr coatings
title_sort Morphological, structural, microhardness and corrosion characterisations of electrodeposited Ni-Mo and Cr coatings
author Lima-Neto,Pedro de
author_facet Lima-Neto,Pedro de
Correia,Adriana N.
Vaz,Gustavo L.
Casciano,Paulo N. S.
author_role author
author2 Correia,Adriana N.
Vaz,Gustavo L.
Casciano,Paulo N. S.
author2_role author
author
author
dc.contributor.author.fl_str_mv Lima-Neto,Pedro de
Correia,Adriana N.
Vaz,Gustavo L.
Casciano,Paulo N. S.
dc.subject.por.fl_str_mv Ni-Mo
Cr
electrodeposition
corrosion
heat treatment
microhardness
topic Ni-Mo
Cr
electrodeposition
corrosion
heat treatment
microhardness
description The corrosion resistance of electrodeposited Cr and Ni-Mo coatings and the influence of heat treatment on the crystallographic structure, morphology and microhardness properties were investigated here. The characterisations were carried out using scanning electron microscopy (SEM), X-ray diffraction (XRD) and energy dispersive X-ray analysis (EDX) techniques. Corrosion tests were performed at room temperature in 10-1 mol dm-3 NaCl solutions and by potentiodynamic linear polarization technique.TheMo content in the layer and current efficiency increased with the molybdate ion concentration in the plating solution, while the surface morphology evolved from rough and homogeneous to cracked surface with the increase of the amount of Mo in the layer. The electrochemical corrosion tests showed that the Cr coatings have better corrosion resistance than the Ni-Mo coatings in chloride medium and that all the studied coatings corrode in chloride medium. Ni-13Mo coating has the nobler corrosion behavior among the studied Ni-Mo coatings. The microhardness of the Ni-13Mo coatings increased as the annealing temperature increased which is related with the precipitation of Ni, Ni4Mo and NiMo phases during the heat treatment of this coating. Ni-13Mo coating is a potential substitute for chromium coating in industrial applications when operating at temperatures higher than 100 ºC and good microhardness properties are required.
publishDate 2010
dc.date.none.fl_str_mv 2010-01-01
dc.type.driver.fl_str_mv info:eu-repo/semantics/article
dc.type.status.fl_str_mv info:eu-repo/semantics/publishedVersion
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dc.identifier.uri.fl_str_mv http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532010001000024
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dc.language.iso.fl_str_mv eng
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dc.relation.none.fl_str_mv 10.1590/S0103-50532010001000024
dc.rights.driver.fl_str_mv info:eu-repo/semantics/openAccess
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dc.format.none.fl_str_mv text/html
dc.publisher.none.fl_str_mv Sociedade Brasileira de Química
publisher.none.fl_str_mv Sociedade Brasileira de Química
dc.source.none.fl_str_mv Journal of the Brazilian Chemical Society v.21 n.10 2010
reponame:Journal of the Brazilian Chemical Society (Online)
instname:Sociedade Brasileira de Química (SBQ)
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reponame_str Journal of the Brazilian Chemical Society (Online)
collection Journal of the Brazilian Chemical Society (Online)
repository.name.fl_str_mv Journal of the Brazilian Chemical Society (Online) - Sociedade Brasileira de Química (SBQ)
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