Numerical simulation of electrochemical behavior for naval steel microstructure exploiting experimental polarization data

Κουζούμης, Κωνσταντίνος; Kouzoumis, Konstantinos

dc.contributor.author	Κουζούμης, Κωνσταντίνος	el
dc.contributor.author	Kouzoumis, Konstantinos	en
dc.date.accessioned	2016-12-13T08:46:02Z
dc.date.issued	2016-12-13
dc.identifier.uri	https://dspace.lib.ntua.gr/xmlui/handle/123456789/44133
dc.identifier.uri	http://dx.doi.org/10.26240/heal.ntua.13886
dc.rights	Αναφορά Δημιουργού-Μη Εμπορική Χρήση-Όχι Παράγωγα Έργα 3.0 Ελλάδα	*
dc.rights.uri	http://creativecommons.org/licenses/by-nc-nd/3.0/gr/	*
dc.subject	Modeling	en
dc.subject	Electrochemistry	en
dc.title	Numerical simulation of electrochemical behavior for naval steel microstructure exploiting experimental polarization data	en
heal.type	bachelorThesis
heal.classification	Επιστήμη υλικών	el
heal.classificationURI	http://data.seab.gr/concepts/840868f9d668cd136ec6f074902084034906c943
heal.dateAvailable	2017-12-12T22:00:00Z
heal.language	en
heal.access	free
heal.recordProvider	ntua	el
heal.publicationDate	2016-10-25
heal.abstract	The aim of the present Diploma Thesis is the simulation of the electrochemical behavior for naval steel microstructure with the exploitation of experimental polarization data. For the model development the simulation of the microstructure was also required as an input parameter.In particular the electrochemical behavior of AH36 steel, which consists of a-phase ferrite and pearlitic micro – constituent, in NaCl 3.5% environments was simulated, concerning the polarization curves obtained by potentiostatic method. The prediction of electrochemical behavior of this alloy was simulated taking into account the electrochemical behavior of its constituting different microstructures: ferrite a-phase and pearlite micro-constituent. For this reason, electrochemical experiments, potentiostatic polarization, was conducted on AH36 ferritic-pearlitic steel alloy, Ferrite specimen and Perlite specimen, where ferrite and pearlite are the constituting metallographic phases of AH36.The Tafel curves obtained from the electrochemical experiments performed, showe that Ferrite presents lower values for Ecorr than Pearlite, indicating that ferrite exhibits higher tendency for corrosion. This difference implies that it would be possible for a galvanic couple to be formed at the microstructural level. More specifically, in ferrite – pearlite steel alloys exposed to corrosion, the ferrite grains could act as anodes providing electrons towards the pearlitic regions (acting as cathodes). Hence, this behavior could be simulated according to the amount of each phase within the alloy‘s microstructure. For the simulation of the ferritic-pearlitic microstructure of AH36 steel, the Voronoi tessellation approach was employed. The ferrite and the pearlite amounts on the model’s application regarding the microstructure deviates by 0.36% from the actual microstructure, which is considered adequately acceptable. The modeled and the experimental polarization curves for AH36 ferritic-pearlitic steel appear to be similar. The same conclusion is deduced for the Ecorr, icorr electrochemical parameters concerning the modeled and the experimental curves. The prediction regarding the metal’s dissolution from the developed model, shows that the electrolyte has penetrated against the metal‘s domain. This denotes that the metallic regions have dissolved permitting the solution to invade. The agreement between the model’s polarization curves and the experimental ones, along with the agreement in the obtained parameters Ecorr, icorr prove that the assumption of the electrochemical behavior of AH36 ferritic-pearlitic steel being defined by the electrochemical behavior of its constituting microstructures is fairly stated, as long as it is supported by a concrete simulation of the micro-structure.	en
heal.advisorName	Παντελής, Δημήτριος	el
heal.committeeMemberName	Παντελής, Δημήτριος	el
heal.committeeMemberName	Τσούβαλης, Νικόλαος	el
heal.committeeMemberName	Μανωλάκος, Δημήτριος	el
heal.academicPublisher	Εθνικό Μετσόβιο Πολυτεχνείο. Σχολή Ναυπηγών Μηχανολόγων Μηχανικών. Τομέας Θαλάσσιων Κατασκευών. Εργαστήριο Ναυπηγικής Τεχνολογίας	el
heal.academicPublisherID	ntua
heal.numberOfPages	160 σ.	el
heal.fullTextAvailability	true