Corrosion investigation of longitudinal direction of corroded main cable on an actual suspension bridge

<p>In this study, in order to clarify the corrosion condition and longitudinal change of an actual suspension bridge main cable used for more than 50 years, the disassembly investigation was conducted based on the corrosion evaluation criteria applying the rust composition analysis. In the 6 ropes composing the main cable, from the comparison result of the disassembly investigation of all ropes, it was confirmed that the corrosion level on the rope surface tended to be relatively higher than inside. In addition, from the investigation results of the disassembly and the corrosion distribution rate in the longitudinal direction, it was clarified that even if the inside of the strand that composing rope was corroded at a certain cross section, the corrosion condition was changed during the twisting process. Furthermore, it was confirmed that the corrosion tends to progress between the outer strands.</p>

Corrosion Investigation of Mild Steel in Aqueous Hydrochloric Acid Environment Using N-(Naphthalen-1-yl)-1-(4-Pyridinyl)Methanimine Complemented with Antibacterial Studies

The inhibitive performance of N-(naphthalen-1-yl)-1-(4-pyridinyl)methanimine Schiff base on mild steel corrosion in one molar hydrochloric acid environment was investigated by utilizing weight loss techniques. N-(naphthalen-1-yl)-1-(4-pyridinyl)methanimine has significant inhibitive performance on the mild steel corrosion in the corrosive medium. The effect of immersion time (1-24 h) and temperature (303 to 333 K) on the behavior of mild steel corrosion in the absence and presence of the N-(naphthalen-1-yl)-1-(4-pyridinyl)methanimine have also been investigated. The adsorption of N-(naphthalen-1-yl)-1-(4-pyridinyl)methanimine molecules on the surface of mild steel follows Langmuir adsorption isotherm. The surface morphology of the mild steel coupon was investigated by scanning electron microscopy. The antibacterial efficiencies of N-(naphthalen-1-yl)-1-(4-pyridinyl)methanimine for gram-negative bacteria, namely Escherichia coli, and gram-positive bacteria, namely Staphylococcus aureus was studied. The antibacterial activity findings exhibited that the N-(naphthalen-1-yl)-1-(4-pyridinyl)methanimine has significant antibacterial efficiencies against tested microorganisms.

Effects of the Different Solid Deposits on the Corrosion Behavior of Pure Fe in Water Vapor at 500°C

A comprehensive corrosion investigation of pure Fe in an environment of solid sodium salt deposit (i.e., NaCl or Na2SO4) with mixtures of H2O and O2 at 500°C was conducted by mass gain measurement, X-ray diffraction (XRD), scanning electron microscope (SEM), potentiodynamic polarization, and electrochemical impedance spectroscopy (EIS). The results showed that corrosion rates were accelerated with solid NaCl or Na2SO4 deposit due to their reaction with the formed protective scale of Fe2O3 and subsequently resulted in its breakdown. The corrosion rate of pure Fe with solid NaCl is higher than that with solid Na2SO4 because of the lower activation energy (Ea) for chemical reaction of Fe in solid NaCl+H2O+O2 (i.e., 140.5 kJ/mol) than that in solid Na2SO4+H2O+O2 (i.e., 200.9 kJ/mol). Notably, the electrochemical corrosion rate of pure Fe with solid NaCl deposit, 1.16×10−4 A/cm2, was a little lower than that with solid Na2SO4 deposit.

Copper and aluminum electric corrosion investigation and intermetallics disappearance in Cu-Al system analysis

Copper and aluminum electric corrosion is investigated experimentally. It is founded that copper corrosion is higher than aluminum corrosion. Intermetallics disappearance rate in Cu-Al system is analyzing theoretically. Literature experimental data are used for analysis.