H. Fattahi, M. H. Shariat,
Volume 5, Issue 1 (3-2008)
Abstract
Abstract: In chloride salt solutions, titanium alloys exhibit reasonably high pitting potentials as
high as +10 V (vs. Ag/AgCl) at room temperatures. On the other hand, anodic pitting potentials
are significantly lower in bromide solutions. In this study, pitting corrosion of commercially pure
titanium in aqueous NaBr solution of 0.1 M concentration at room temperature was studied and
the effect of an external magnetic field oriented both parallel and perpendicular to electrode
surface was investigated. Cyclic potentiodynamic and potentiostatic polarization tests were
carried out. Anodic breakdown potential of +1.45 V (vs. Ag/AgCl) obtained in the absence of
magnetic field, decreasing to +1.11 V in the presence of a 0.05 T parallel magnetic field. The
perpendicular magnetic field actually did not affect the breakdown potential. Applying of an
external magnetic field, independent of its orientation, shifted the repassivation potential
approximately 150 mV in the positive direction. SEM microscopy observations of sample surfaces
indicated that applying of magnetic field results in some variations in the pit shapes and their
sizes.
P. Samadi, M. Reza Afshar, M. R. Aboutalebi, S. H. Seyedein,
Volume 9, Issue 1 (3-2012)
Abstract
Electrochemical coating processes are significantly affected by applied magnetic fields due to the generation of electromagnetic forces. The present research work has been undertaken to study the effect of coating parameters such as current density and alumina concentration on the characteristics of Ni-Al2O3 composite coating under static magnetic field. Ni-Al2O3 composite coating was applied on a mild steel substrate using conventional Watts solution containing Al2O3 particles with and without magnetic field. The coating microstructure and Al2O3 particle density in the coating layer were examined by scanning electron microscopy (SEM). It was found that the applied magnetic field made the coating structure finer and leads to the increases of the particle content in the coating. However, the results confirmed that the magnetic forces inversely affected the particle density in the coating at higher current density than that of normal coating process.
