WANG Hua
,
LIANG Chenghao
钢铁研究学报(英文版)
The effects of sulfate reduced bacterium (SRB) on the corrosion behavior of 10CrMoAl steel in seawater were studied by chemical immersion, potentiodynamic polarization, electrochemical impedance spectroscopy measurement, and scanning electron microscope techniques. The results show that the content of element sulfur in the corrosion product of 10CrMoAl steel in seawater with SRB is up to 923%, which is higher than that of the same in sterile seawater. Xray diffraction demonstrates that the main corrosion product is FeS. SRB increases the corrosion rate by anodic depolarization of the metabolized sulfide product. SEM observation indicates that the corrosion product is not distributed continuously; in addition, bacilliform sulfatereduced bacterium accumulates on the local surface of 10CrMoAl steel. Hence, SRB enhances sensitivity to the localized corrosion of 10CrMoAl steel in seawater.
关键词:
sulfate reduced bacterium;10CrMoAl steel;localized corrosion
LIANG Chenghao
,
HU Xianqi
钢铁研究学报(英文版)
The inhibition performance of enhancedMo inhibitor for carbon steel in 55% LiBr solution was measured by means of chemical immersion, electrochemical measurements, and physical detection technologies. Results indicated that enhancedMo inhibitor showed excellent inhibition performance of carbon steel in 55% LiBr solution, especially at high temperature. With increasing the temperature of solution from 160 ℃ to 240 ℃, the corrosion rates of carbon steel increased from 1767 μm/a to 3307 μm/a. EnhancedMo inhibitor might improve the anodic polarization performance of carbon steel and widen the passive potential region of carbon steel in 55% LiBr solution. EnhancedMo inhibitor belongs to anodic inhibitor. In 55% LiBr solution, the relationship between corrosion current density icorr and corrosion potential Ecorr of carbon steel accorded with the equation lgicorr=-266-354Ecorr, and the value of cathodic Tafel constant βc for the H2 reaction was 282 mVSCE. When 55% LiBr solution contained enhancedMo inhibitor, a passive film comprising Fe3O4 and MoO2 was formed on the carbon steel surface by electrochemical reactions. The corrosion of carbon steel might be retarded by this protective film, and the anticorrosion performance of carbon steel in 55% LiBr solution might be improved by enhancedMo inhibitor.
关键词:
corrosion;enhancedMo inhibitor;carbon steel
