Study on the galvanic corrosion phenomenon of cladding steel bars

Abstract

To explore corrosion law of bimetallic interface of a new type of steel bars, which cladded in stainless steel by hot rolling process, COMSOL Multiphysics electrochemical corrosion module, as a simulation tool, was used for studying the electrode potential distribution, current density distribution and electrode surface morphology change during the corrosion process at the reinforced bimetal bonding surface of cladding layer combining with the surface of the electrode potential distribution in the process of corrosion, the current density distribution and the electrode surface morphology change in bimetallic interface of our new type steel bars , at the same time use the salt fog corrosion, equipment corrosion test was carried out on the cladding steel, used to verify the accuracy of the simulation results. The results suggested that the coating electrode potential of stainless steel was obviously higher than that of carbon steel, in combination with surface constitute a pair of electrodes, the increased incidence of corrosion of carbon steel side and in the simulation and experiment are form a “V” corrosion pits, by measuring found that, in the condition of the mass fraction of 5% salt spray and 50 °C temperature, average surface cladding steel corrosion rate is 2.2 * 10 ^ (-3) mm/h.