The alumina ceramic coatings were prepared on aluminum alloy using micro-plasma oxidation. The structure and morphologies of ceramic coatings were studied by X-ray diffraction (XRD) and scanning electron microscope (S...The alumina ceramic coatings were prepared on aluminum alloy using micro-plasma oxidation. The structure and morphologies of ceramic coatings were studied by X-ray diffraction (XRD) and scanning electron microscope (SEM), and then its formation process was investigated. The results of XRD reveal that with increasing oxidation time the content of decreases, and in which the content of al reaction occurs between the aluminum from the substrate and the oxygen and other ions from the electrolyte. The reaction products then are propelled away from the inner-wall of the discharging channels. Finally, these products agglomerate in the inner-wall of the discharging channels and on the surface near the discharging channels to produce the ceramic coatings. The change of ceramic coatings thickness with increasing oxidation time divides into two stages, and the final thickness is formed in first stage. With increasing current density the final thickness of ceramic coatings increases.展开更多
基金The project supported by International Science and Technology Cooperation Key Program(No.2005DFA50450)Program of Educational Committee of Jiangxi Province(No.[2005]322[2006]309)
文摘The alumina ceramic coatings were prepared on aluminum alloy using micro-plasma oxidation. The structure and morphologies of ceramic coatings were studied by X-ray diffraction (XRD) and scanning electron microscope (SEM), and then its formation process was investigated. The results of XRD reveal that with increasing oxidation time the content of decreases, and in which the content of al reaction occurs between the aluminum from the substrate and the oxygen and other ions from the electrolyte. The reaction products then are propelled away from the inner-wall of the discharging channels. Finally, these products agglomerate in the inner-wall of the discharging channels and on the surface near the discharging channels to produce the ceramic coatings. The change of ceramic coatings thickness with increasing oxidation time divides into two stages, and the final thickness is formed in first stage. With increasing current density the final thickness of ceramic coatings increases.
