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dc.contributor.advisorYasuda, H.eng
dc.contributor.authorYoung, Kevin, 1977-eng
dc.date.issued2004eng
dc.date.submitted2004 Falleng
dc.descriptionThe entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file.eng
dc.descriptionTitle from title screen of research.pdf file viewed on (June 30, 2006)eng
dc.descriptionIncludes bibliographical references.eng
dc.descriptionVita.eng
dc.descriptionThesis (M.S.) University of Missouri-Columbia 2004.eng
dc.descriptionDissertations, Academic -- University of Missouri--Columbia -- Chemical engineering.eng
dc.description.abstractElectrochemical impedance spectroscopy (EIS) during an accelerated corrosion (GM scab) test was used to differentiate between good and poor coating systems on coldrolled steel (CRS). The best coating was determined to be a cathodic Ecoat/ trimethylsilane (TMS) plasma polymer/oxide-free steel surface having an impedance modulus at low frequency of 109 ohms throughout the entire corrosion test. A spray paint primer and surface oxides both contributed to a degradation of corrosion protection evident from a significant drop in impedance (106_ ). With samples of known corrosion resistance, equivalent circuits were used to relate circuit elements to individual chemical processes taking place and identify the major factors contributing to failure of the coating. Two models (with and without plasma polymer film) were proposed and a good correlation to the EIS data was shown by a good visual plot fit and low chi squared values (<10-3). It was determined that the performance of the plasma polymer and conditions at the PP/steel interface are the major factors influencing the coating performance. The good coating system maintained a low double layer capacitance (10-9 F) and high charge transfer resistance (109_ ) relating to good adhesion at the coating/metal interface. The other samples, which exhibited poor adhesion, had a much higher capacitance (10-6 F) meaning water pool formation has created a water/metal interface. This in turn allows salt penetration for a higher corrosion rate showing up in the lower resistance (106_ ).eng
dc.identifier.merlinb5585039xeng
dc.identifier.urihttp://hdl.handle.net/10355/4104
dc.languageEnglisheng
dc.publisherUniversity of Missouri--Columbiaeng
dc.relation.ispartof2004 Freely available theses (MU)eng
dc.relation.ispartofcollectionUniversity of Missouri--Columbia. Graduate School. Theses and Dissertationseng
dc.subject.lcshPlasma polymerizationeng
dc.subject.lcshProtective coatingseng
dc.titleEquivalent circuit modeling of TMS plasma polymer coating system on cold-rolled steeleng
dc.typeThesiseng
thesis.degree.disciplineChemical engineering (MU)eng
thesis.degree.grantorUniversity of Missouri--Columbiaeng
thesis.degree.levelMasterseng
thesis.degree.nameM.S.eng


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