3847

186 دكتري

دكتري

مواد

اصفها ن: دانشگاه صنعتي اصفهان، دانشكده مواد

1386

نه، 111، [II]ص.: مصور، جدول، نمودار

ص. ع. به فارسي و انگليسي

1396/03/06

كتابنامه

مواد

مهندسي مواد

ID186 دكتري

به فارسي و انگليسي: قابل رويت در نسخه ديجيتال

۳AbstractElectrochemical behavior of mild steel having different surface roughness inpolymerization solution containing oxalic acid and pyrrole monomer were studied usingpotentiodynamic polarization technique Curves for converting polymerization potential tocurrent density were obtained and different potential stages in these curves werecharacterized In order to define the mechanisms of coating formation in differentpotentials and determining various stages electrochemical impedance spectroscopy testswere performed at various potentials Surface morphology and structure of specimensprepared in different potentials were investigated using scanning electron microscopy andx ray diffraction techniques respectively Results obtained revealed that in each potentialrange as potential increases the following mechanisms are prevailed a dissolution ofpassive layer without oxidation of monomer b oxidation of monomer to oligomers withhigh solubility without coating formation c formation of planar polypyrrole coating withcrystalline nucleates d formation of semiplanar polypyrrole coating e polypyrrolecoating with cauliflower morphology Infrared spectroscopy studies of coatings prepared atvarious potential ranges were also carried out X ray diffraction pattern of polypyrrolecoatings revealed that the crystallinity of semicrystalline polypyrrole is 68 Elementalanalysis of coatings revealed that the ratio of pyrrole to oxalate ions in amorphouspolypyrrole is 5 to 1 while in crystalline one is 4 to 1 Surface topography of coatings wasstudied using atomic force microscopy Corrosion behavior of polypyrrole coated mildsteel with various morphologies was investigated using potentiodynamic polarizationtechniques Results showed that corrosion behavior of specimens with semicrystallinepolypyrrole coating was superior to amorphous one

محمد علي گلعذار

شادپور ملك پور

فرامرز افشار طارمي، احمد ساعتچي، محسن صارمي، كيوان رئيسي