In this work,the electrochemical behaviors of SAM2X5 Fe-based amorphous alloy coating and hard chromium coating were comparatively studied in 3.5 wt% NaCl solution.In comparison with the hard chromium coating,the SAM2...In this work,the electrochemical behaviors of SAM2X5 Fe-based amorphous alloy coating and hard chromium coating were comparatively studied in 3.5 wt% NaCl solution.In comparison with the hard chromium coating,the SAM2X5 coating exhibited a wider and stable passive region with lower passive current density in the potentiodynamic polarization and showed a considerably lower current density at different anodic potentials in the potentiostatic polarization.In order to understand the passivation mechanism of the Fe-based amorphous coating,the components of the passive films formed at various polarization potentials were examined by X-ray photoelectron spectroscopy.The synergistic effect of Mo,W,Mn and Cr in the passive films was systemically analyzed.It has been revealed that Mo and W facilitate the formation of compact and stable Cr2O3 passive film at lower potentials,and the substantial enrichment of Mn in the passive film enhances the passivation ability at relatively higher potentials.The deep understanding of the passivation characteristics in multicomponent alloy systems could provide a guide for the design of corrosion-resistant amorphous alloy coatings for engineering applications.展开更多
In this paper, the synthetic effect ofCr, Mo and Y on corrosion resistance was explored, and the YCr/Mo value was employed to evaluate the corrosion resistance. The composition of amorphous alloy was designed by mixin...In this paper, the synthetic effect ofCr, Mo and Y on corrosion resistance was explored, and the YCr/Mo value was employed to evaluate the corrosion resistance. The composition of amorphous alloy was designed by mixing the Fe41Co7Cr15Mo14C15B6Y2 （BMG1） with good glass forming ability （GFA） and Fe50Cr22B23Ni5.4 with a high corrosion resistance at 9：1 ratio. At the same time, the contents of Y, Mo and Cr were fine-tuned. The electrochemical tests demonstrated that the passivation current density decreased with the increase of the yCr/Mo value. The passivation current density of Fe-based amorphous alloy was reduced by about half an order of magnitude. The fitting result showed that the logarithm ofpassivation current density （I） and the YCr/Mo value （X） were logarithmic relationship, and the fitting equation was I=-5.649＋4.904× 1015 e 17.52x. The X-ray photoelectron spectroscopy （XPS） results showed that the yC,/Mo value played a key role in stability of passive films. When the yCr/Mo value Was low, the Cr6＋ ion, Mo6＋ ion were enriched in the initial stage of passivation process, then leading to the increase passivation current density. However, when the YCr/Mo value was high, the low-valence Fe2-, Cr3＋, and Mo4＋ ion were enriched more easily, which result in small passivation current densities and more stable passive films.展开更多
基金supported by the National Natural Science Foundation of China (Nos. 51471166, 51131006 and 51171119)the College Youth Scholar Fostering Program of Liaoning Province (No. LJQ2014015)
文摘In this work,the electrochemical behaviors of SAM2X5 Fe-based amorphous alloy coating and hard chromium coating were comparatively studied in 3.5 wt% NaCl solution.In comparison with the hard chromium coating,the SAM2X5 coating exhibited a wider and stable passive region with lower passive current density in the potentiodynamic polarization and showed a considerably lower current density at different anodic potentials in the potentiostatic polarization.In order to understand the passivation mechanism of the Fe-based amorphous coating,the components of the passive films formed at various polarization potentials were examined by X-ray photoelectron spectroscopy.The synergistic effect of Mo,W,Mn and Cr in the passive films was systemically analyzed.It has been revealed that Mo and W facilitate the formation of compact and stable Cr2O3 passive film at lower potentials,and the substantial enrichment of Mn in the passive film enhances the passivation ability at relatively higher potentials.The deep understanding of the passivation characteristics in multicomponent alloy systems could provide a guide for the design of corrosion-resistant amorphous alloy coatings for engineering applications.
基金Project supported by the National Natural Science Foundation of China(51261021)Science and Technology Landing Plan Project of Jiangxi Province(KJLD13056)
文摘In this paper, the synthetic effect ofCr, Mo and Y on corrosion resistance was explored, and the YCr/Mo value was employed to evaluate the corrosion resistance. The composition of amorphous alloy was designed by mixing the Fe41Co7Cr15Mo14C15B6Y2 （BMG1） with good glass forming ability （GFA） and Fe50Cr22B23Ni5.4 with a high corrosion resistance at 9：1 ratio. At the same time, the contents of Y, Mo and Cr were fine-tuned. The electrochemical tests demonstrated that the passivation current density decreased with the increase of the yCr/Mo value. The passivation current density of Fe-based amorphous alloy was reduced by about half an order of magnitude. The fitting result showed that the logarithm ofpassivation current density （I） and the YCr/Mo value （X） were logarithmic relationship, and the fitting equation was I=-5.649＋4.904× 1015 e 17.52x. The X-ray photoelectron spectroscopy （XPS） results showed that the yC,/Mo value played a key role in stability of passive films. When the yCr/Mo value Was low, the Cr6＋ ion, Mo6＋ ion were enriched in the initial stage of passivation process, then leading to the increase passivation current density. However, when the YCr/Mo value was high, the low-valence Fe2-, Cr3＋, and Mo4＋ ion were enriched more easily, which result in small passivation current densities and more stable passive films.
