Effects of KMnO_4 on microstructure and corrosion resistance of microarc oxidation coatings on 2024

来源 :中南大学学报 | 被引量 : 0次 | 上传用户:Tiffany100
下载到本地 , 更方便阅读
声明 : 本文档内容版权归属内容提供方 , 如果您对本文有版权争议 , 可与客服联系进行内容授权或下架
论文部分内容阅读
Microarc oxidation (MAO) coatings were prepared on 2024 aluminum alloy in a Na_2SiO_3-KOH electrolyte with KMnO_4 addition varying from 0 to 4 g/L. The microstructure and phases of the coatings were characterized by scanning electron microscopy (SEM) and X-ray diffractometry (XRD), respectively. The corrosion resistance of MAO coatings was evaluated by electrochemical potentiodynamic polarization in 5% (mass fraction) NaCl solution. The results show that when KMnO_4 is added into base electrolyte, the growth speed of oxide coatings is increased obviously. The main phase of oxide coatings is Al_2O_3, and the contents of MnO_2 and Mn_2AlO_4 phases are increased at the top of oxide coatings with increasing the concentration of KMnO_4. The solute elements participate in forming the oxide coatings. When a proper concentration of KMnO_4 (2.5 g/L) is added into the base solution, the micropores of the MAO coatings are small and compact, and the corrosion resistance of oxide coatings is increased largely.
其他文献
The mercury sulfidation experiments were conducted in the pH range from 1 to 13. The results show that Hg(Ⅱ) reacted with equimolar S(Ⅱ) has the lowest remain
A new monostatic army system taking advantage of diverse waveforms to improve the performance of underwater target localization is proposed.Unlike the coherent
Many practical systems in physics,biology,engineering and information science exhibit impulsive dynamical behaviors due to abrupt changes at certain instants du
Nickel-tungsten/carbon nanotube nanocomposite layers with high content and uniform dispersion of carbon nanotubes were fabricated using pulsed electrodeposition
A prediction based energy-efficient target tracking protocol in wireless sensor networks (PET) was proposed for tracking a mobile target in terms of sensing and
The Mo substrate with Zr interlayer, namely composite substrate, was employed to solve the problem of crack formation in the freestanding diamond film depositio
A new kind of volume control hydraulic press that combines the advantages of both hydraulic and SRM (switched reluctance motor) driving technology is developed.
The microstructure and precipitation characteristics of 22Cr-14W-2Mo superalloys added with various La contents have been studied by SEM, TEM and EDX. It is fou
A linear matrix inequality (LMI)-based sliding surface design method for integral sliding mode control of uncertain timedelay systems with mismatching uncertain
The exponential stability in mean square and stabilization problems for Ito stochastic switched systems with multiple time-delays are investigated.The system po