Micro arc oxidation(MAO) and electrophoretic deposition(EPD) process are employed to fabricate a dense coating on magnesium alloy to protect it from corrosion in engineering application. The EPD film changes the dampi...Micro arc oxidation(MAO) and electrophoretic deposition(EPD) process are employed to fabricate a dense coating on magnesium alloy to protect it from corrosion in engineering application. The EPD film changes the damping characteristic of magnesium alloy, and both the MAO and EPD process change the bending stiffness of samples being treated. Damping loss factor(DLF) test and sound transmission experiments were carried out for AZ31 B magnesium alloy with coating fabricated by MAO and EPD processes. The results indicate that DLF is improved in frequency range from 0-850 Hz. Bending stiffness of the samples is improved with MAO and EPD treatment. As a result, the sound transmission loss(LST) is improved in the stiffness control stage of the sound transmission verse frequency curve. To the samples by electrophoresis process, the LST is improved in frequency range from 2500-3200 Hz, because the damping loss factor is improved with EPD process. The results are useful for the surface treatment to enhance the damping loss factor, LST and widespread application of magnesium alloy while improving the corrosion resistance.展开更多
Fe-Al intermetallics with remarkable high-temperature intensity and excellent erosion, high-temperature oxidation and sulfuration resistance are potential low cost high-temperature structural materials. But the room t...Fe-Al intermetallics with remarkable high-temperature intensity and excellent erosion, high-temperature oxidation and sulfuration resistance are potential low cost high-temperature structural materials. But the room temperature brittleness induces shape difficult and limits its industrial application. The Fe-Al intermetallic coatings were prepared by high velocity arc spraying technology with cored wire on 20G steel, which will not only obviate the problems faced in fabrication of these alloys into useful shapes, but also allow the effective use of their outstanding high-temperature performance. The Fe-Al/WC intermetallic composite coatings were prepared by high velocity arc spraying technology on 20G steel and the oxidation performance of Fe-Al/WC composite coatings was studied by means of thermogrativmetic analyzer at 450, 650 and 800℃. The results demonstrate that the kinetics curve of oxidation at three temperatures approximately follows the logarithmic law. The composition of the oxidized coating is mainly composed of Al2O3, Fe2O3, Fe3O4 and FeO. These phases distribute unevenly. The protective Al2O3 film firstly forms and preserves the coatings from further oxidation.展开更多
Fe-Al/Cr3C2 coatings were sprayed on low steel by high velocity arc spraying（HVAS） technology. The influences of oxides on erosion, corrosion and wear behavior for high velocity arc sprayed Fe-Al/Cr3C2 coatings were...Fe-Al/Cr3C2 coatings were sprayed on low steel by high velocity arc spraying（HVAS） technology. The influences of oxides on erosion, corrosion and wear behavior for high velocity arc sprayed Fe-Al/Cr3C2 coatings were studied. The results show that HVAS-sprayed Fe-Al/Cr3C2 coatings have good erosion, heat corrosion and wear resistance. The erosion resistance improves with the increase of the temperature. On one hand, the ferrous oxides are incompact, so they peel off the surface of the coatings easily during the high temperature erosion. On the other hand, compact Al2O3 films on the surface can protect the coatings.展开更多
基金Project(2011BAE22B05)supported by National Technology R&D Program in the 12th Five year Plan of ChinaProject(2011DFA50900)supported by the Canada-China-USA Collaborative Research&Development ProjectProject(51071121)supported by the National Natural Science Foundation of China
文摘Micro arc oxidation(MAO) and electrophoretic deposition(EPD) process are employed to fabricate a dense coating on magnesium alloy to protect it from corrosion in engineering application. The EPD film changes the damping characteristic of magnesium alloy, and both the MAO and EPD process change the bending stiffness of samples being treated. Damping loss factor(DLF) test and sound transmission experiments were carried out for AZ31 B magnesium alloy with coating fabricated by MAO and EPD processes. The results indicate that DLF is improved in frequency range from 0-850 Hz. Bending stiffness of the samples is improved with MAO and EPD treatment. As a result, the sound transmission loss(LST) is improved in the stiffness control stage of the sound transmission verse frequency curve. To the samples by electrophoresis process, the LST is improved in frequency range from 2500-3200 Hz, because the damping loss factor is improved with EPD process. The results are useful for the surface treatment to enhance the damping loss factor, LST and widespread application of magnesium alloy while improving the corrosion resistance.
文摘Fe-Al intermetallics with remarkable high-temperature intensity and excellent erosion, high-temperature oxidation and sulfuration resistance are potential low cost high-temperature structural materials. But the room temperature brittleness induces shape difficult and limits its industrial application. The Fe-Al intermetallic coatings were prepared by high velocity arc spraying technology with cored wire on 20G steel, which will not only obviate the problems faced in fabrication of these alloys into useful shapes, but also allow the effective use of their outstanding high-temperature performance. The Fe-Al/WC intermetallic composite coatings were prepared by high velocity arc spraying technology on 20G steel and the oxidation performance of Fe-Al/WC composite coatings was studied by means of thermogrativmetic analyzer at 450, 650 and 800℃. The results demonstrate that the kinetics curve of oxidation at three temperatures approximately follows the logarithmic law. The composition of the oxidized coating is mainly composed of Al2O3, Fe2O3, Fe3O4 and FeO. These phases distribute unevenly. The protective Al2O3 film firstly forms and preserves the coatings from further oxidation.
文摘Fe-Al/Cr3C2 coatings were sprayed on low steel by high velocity arc spraying（HVAS） technology. The influences of oxides on erosion, corrosion and wear behavior for high velocity arc sprayed Fe-Al/Cr3C2 coatings were studied. The results show that HVAS-sprayed Fe-Al/Cr3C2 coatings have good erosion, heat corrosion and wear resistance. The erosion resistance improves with the increase of the temperature. On one hand, the ferrous oxides are incompact, so they peel off the surface of the coatings easily during the high temperature erosion. On the other hand, compact Al2O3 films on the surface can protect the coatings.
