Effect of magnetic field on the oxide protective layer in carbon steel piping

To explore the mitigation method of flow-accelerated corrosion using permanent magnet, this study was performed to evaluate the effect of magnetic field on the corrosion reaction of carbon steel at various temperatures. Rotating cylinder electrode apparatus with attached heating was made to simulate fluid flow, and to perform polarization test with permanent magnet. Polarization tests were carried out at various temperatures and magnetic field intensities and the results were analyzed by linear method. Corrosion potential increased with increasing temperature without magnetic field, while the potential was maintained at almost same value with magnetic field. On the other hand, corrosion current density increased with temperature regardless of magnetic field. The magnetic field enhanced the corrosion rate at room temperature. At 80 .deg. C the magnetic field effect did not appear up to 1,750 Gauss. At 80 .deg. C the effect of magnetic field on the corrosion reaction turned out smaller than at room temperature. If the effect of magnetic field on the corrosion reaction is reduced with increasing temperature, and the magnetic field increase the mechanical stability of oxide film as the result of previous research. The magnetic method may be favorable as a mitigation method of the flow accelerated corrosion