A systematic investigation was carried out to discuss the corrosion and tribocorrosion behaviors of Hastelloy C276 alloy sliding against Al2O3 pin in artificial seawater, using a pin-on-disk tribometer integrated with...A systematic investigation was carried out to discuss the corrosion and tribocorrosion behaviors of Hastelloy C276 alloy sliding against Al2O3 pin in artificial seawater, using a pin-on-disk tribometer integrated with a potentiostat for electrochemical control. The results show that the great decrease of open circuit potential and three orders of magnitude increase of corrosion current density occur caused by friction. There are clearly synergistic effect between corrosion and wear, resulting in corrosion-induced-wear and wear-induced-corrosion in tribocorrosion process. The contribution of pure mechanical wear to total material loss exceeds 70% in all sliding conditions, so mechanical wear is the dominant factor during tribocorrosion. For considering synergistic effect between corrosion and wear, the contribution of wear-induced-corrosion to total material loss is not very high although corrosion rate is greatly accelerated by friction. The fraction of corrosion-induced-wear to the total material loss is high and in the range of 14.6%-20.5% under all sliding conditions.展开更多
The electrochemical and corrosion?wear behaviors of TC4 alloy in artificial seawater were studied. And the influences of electrochemical state on passive behavior, failure mechanism of passive film and corrosion?wear ...The electrochemical and corrosion?wear behaviors of TC4 alloy in artificial seawater were studied. And the influences of electrochemical state on passive behavior, failure mechanism of passive film and corrosion?wear synergy were emphatically analyzed. The corrosion?wear analysis of the alloy was fulfilled by methods of mass loss, electrochemical testing and scanning electron microscope (SEM). It can be observed that the cathodic shift of open circuit potential and three order of magnitude increase of current density can be obtained during corrosion?wear process. Total corrosion?wear loss increases with increasing applied potential, confirming the synergy between wear and corrosion. High polarisation potential results in low coefficient of friction and high corrosion rate. The relative contribution of pure mechanical wear to total material loss deceases obviously with the increase of potential from open circuit potential to 0.9 V during corrosion?wear. Contributions of wear-induced-corrosion and corrosion-induced-wear are significant especially at higher potentials.展开更多
Fenugreek seeds extract was examined as a green corrosion inhibitor for Zn in 2.0 mol/L H2SO4 and 2.0 mol/L HClsolutions by mass loss and electrochemical measurements. Scanning electron microscope （SEM） images show ...Fenugreek seeds extract was examined as a green corrosion inhibitor for Zn in 2.0 mol/L H2SO4 and 2.0 mol/L HClsolutions by mass loss and electrochemical measurements. Scanning electron microscope （SEM） images show that the surfacedamage is decreased in the presence of the inhibitor. X-rays photoelectron spectroscopy （XPS） analysis was performed to identify thecorrosion product, ZnO, and to prove the inhibitor adsorption mechanism. The maximum inhibition efficiency values are 90.7% after1 h and 66.6% after 0.5 h by 200 mL/L of fenugreek extract in H2SO4 and HCl solutions, respectively. Addition of I^- ion greatlyimproves the inhibition efficiency of fenugreek seeds extract for Zn corrosion in HCl due to the synergistic effect. Potentiodynamicpolarization and EIS measurements prove the inhibition ability of fenugreek for Zn corrosion in HCl as indicated by the decreasedcorrosion current density and increased charge transfer resistance values in the presence of fenugreek.展开更多
基金Project(LSL-1310)supported by the Open Project of State Key Laboratory of Solid Lubrication,ChinaProject(51171059)supported by the National Natural Science Foundation of China
文摘A systematic investigation was carried out to discuss the corrosion and tribocorrosion behaviors of Hastelloy C276 alloy sliding against Al2O3 pin in artificial seawater, using a pin-on-disk tribometer integrated with a potentiostat for electrochemical control. The results show that the great decrease of open circuit potential and three orders of magnitude increase of corrosion current density occur caused by friction. There are clearly synergistic effect between corrosion and wear, resulting in corrosion-induced-wear and wear-induced-corrosion in tribocorrosion process. The contribution of pure mechanical wear to total material loss exceeds 70% in all sliding conditions, so mechanical wear is the dominant factor during tribocorrosion. For considering synergistic effect between corrosion and wear, the contribution of wear-induced-corrosion to total material loss is not very high although corrosion rate is greatly accelerated by friction. The fraction of corrosion-induced-wear to the total material loss is high and in the range of 14.6%-20.5% under all sliding conditions.
基金Project(LSL-1310)supported by the Open Project of State Key Laboratory of Solid Lubrication,ChinaProjects(2014QN013,2015GJB004)supported by the Research Foundation of Henan University of Science and Technology,China
文摘The electrochemical and corrosion?wear behaviors of TC4 alloy in artificial seawater were studied. And the influences of electrochemical state on passive behavior, failure mechanism of passive film and corrosion?wear synergy were emphatically analyzed. The corrosion?wear analysis of the alloy was fulfilled by methods of mass loss, electrochemical testing and scanning electron microscope (SEM). It can be observed that the cathodic shift of open circuit potential and three order of magnitude increase of current density can be obtained during corrosion?wear process. Total corrosion?wear loss increases with increasing applied potential, confirming the synergy between wear and corrosion. High polarisation potential results in low coefficient of friction and high corrosion rate. The relative contribution of pure mechanical wear to total material loss deceases obviously with the increase of potential from open circuit potential to 0.9 V during corrosion?wear. Contributions of wear-induced-corrosion and corrosion-induced-wear are significant especially at higher potentials.
文摘Fenugreek seeds extract was examined as a green corrosion inhibitor for Zn in 2.0 mol/L H2SO4 and 2.0 mol/L HClsolutions by mass loss and electrochemical measurements. Scanning electron microscope （SEM） images show that the surfacedamage is decreased in the presence of the inhibitor. X-rays photoelectron spectroscopy （XPS） analysis was performed to identify thecorrosion product, ZnO, and to prove the inhibitor adsorption mechanism. The maximum inhibition efficiency values are 90.7% after1 h and 66.6% after 0.5 h by 200 mL/L of fenugreek extract in H2SO4 and HCl solutions, respectively. Addition of I^- ion greatlyimproves the inhibition efficiency of fenugreek seeds extract for Zn corrosion in HCl due to the synergistic effect. Potentiodynamicpolarization and EIS measurements prove the inhibition ability of fenugreek for Zn corrosion in HCl as indicated by the decreasedcorrosion current density and increased charge transfer resistance values in the presence of fenugreek.
