جستجوی مقالات مرتبط با کلیدواژه « mild steel » در نشریات گروه « مواد و متالورژی »

In this study, camphor sulfonic acid doped polyaniline (CSA PANi) and its nanocomposite with α-Fe2O3 nanoparticles were synthesized using in situ oxidative polymerization and were characterized using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and Field Emission Scanning Electron Microscopy (FESEM). The paste was prepared from synthesized compounds and applied to the pre-treated titanium substrates (sanded and etched) by Dr. Blade method and used as the photoanode for photoelectrochemical cathodic protection of mild steel. The Mott-Schottky analysis was performed to study the type of semiconductor compounds as well as the density of charge carriers. The performance of the prepared photoanodes in the photoelectrochemical cathodic protection of mild steel was studied using electrochemical impedance spectroscopy (EIS) and Tafel polarization. The results showed that the corrosion potential (Ecorr) of mild steel decreased from -706 mV in the case without photoanode connection to -842 mV in the case of connection to Ti / CSA PANI-Fe photoanode under light irradiation, indicating the flux of produced electrons from the photoanode to the surface of mild steel and its cathodic protection. The EIS results also showed that the charge transfer resistance (Rct) for Ti / CSA PANI-Fe was 578.6 Ωcm2 which is less compared to Ti / α-Fe2O3 (874.9 Ωcm2 ) and Ti / CSA PANi (693.4 Ωcm2 ), confirming the low recombination rate of electrons and holes and more flux of electrons to the surface of mild steel and the proper performance of Ti / CSA PANI-Fe photoanode in photoelectrochemical cathodic protection.

Usually, in all applications where an organic coating is applied on the surface, physical and chemical surface preparations need to enhance adhesion and anti-corrosion resistance of the system. Control of surface roughness and chemistry of modified metal by conversion coatings are effective factors in the adhesion properties of organic coatings. In this project, the behavior of anti-corrosion resistance and adhesion of epoxy coatings in the presence and absence of anti-corrosion glass flakes pigments on the surface of steel prepared by applying the zirconium conversion coating and sandblast method were examined. Conversion coating was formed on the surface in the optimum condition of practical parameters. In the next step, the effect of the type of surface preparation on the anti-corrosion resistance and morphology behavior of the coating was investigated using electrochemical tests and atomic force microscope images. It was found that the samples prepared with conversion coating indicated the best anti-corrosion resistance and adhesion strength as a result of the change in the roughness and changing the surface chemistry. Finally, epoxy/glass flake coating with 10% of glass flake was applied on the prepared surface through conversion coating and it was found that adding glass flakes increase the anti-corrosion resistance of the coating and these results confirmed by the salt spray test.

This paper evaluates the function of talc as a reservoir and its ability to absorb and release corrosion inhibitors. In this sense, the performance of released corrosion inhibitors is studied by using electrochemical analysis such as electrochemical impedance spectroscopy as well as surface analysis such as scanning electron microscopy and Energy-dispersive X-ray spectroscopy. Results indicated that talc can adsorb benzothiazole )BTH( as an organic inhibitor and release it in a sodium chloride solution. The trend and magnitude of some parameters including low frequency impedance modulus, polarization resistance and current density revealed the effective role of inhibitor-doped talc in controlling the corrosion of mild steel in sodium chloride solution. The scanning electron microscopy results showed that in the presence of benzothiazole, formation of a compact film on the substrate surface, increasing the corrosion resistance.

Recent research findings have indicated that ionic liquids can be used as effective alternatives for harmful organic inhibitors. In this paper, the effect of an imidazolium based ionic liquid (1,4 -di [1' –methylene- 3'- methyl imidazulim bromide]- benzene) on the corrosion of mild steel in 1M H2SO4 is studied through electrochemical impedance spectroscopy and polarization measurements as well as scanning electron microscopy. The slope of anodic and cathodic branches revealed that the compound is a mixed-type inhibitor. Moreover, the trend and magnitude of the parameters extracted from polarization curves and impedance spectra showed the significant impact of concentration on the performance of inhibitor adsorbing on the metal surface based on Langmuir isotherm.