Anti-corrosion and wear properties of plasma electrolytic oxidation coating formed on high Si content Al alloy by sectionalized oxidation mode

1st International Conference on New Material and Chemical Industry

材料科学;化学工业

Dai, Libin^1 ; Li, Wenfang^1 ; Zhang, Guoge^1 ; Fu, Nianqing^1 ; Duan, Qi^1

School of Materials Science and Engineering, South China University of Technology, Guangzhou

510641, China^1

关键词: Chemical compositions;    Constant current mode;    Constant voltage mode;    High Si content;    Plasma electrolytic oxidation;    Plasma electrolytic oxidation coatings;    Polarization curves;    Tribological performance;   

Others  :  https://iopscience.iop.org/article/10.1088/1757-899X/167/1/012063/pdf
DOI  :  10.1088/1757-899X/167/1/012063

学科分类：材料科学（综合）

来源: IOP

【 摘 要 】

In this study, a uniform and less defective ceramic coating was prepared on high Si content aluminium alloys by a sectionalized plasma electrolytic oxidation (PEO) mode. The PEO process of Al-9 wt. % Si binary alloy was performed under constant current mode followed by constant voltage mode. The surface micrographs and chemical compositions of different samples were analysed by scanning electron microscopy (SEM) and X-ray diffraction (XRD), respectively. Micro-hardness and reciprocal-sliding testers were used to measure the coatings hardness and tribological performance. It was found that the sectionalized PEO mode could produce hard and anti-friction passive oxide layers with smaller holes and fewer cracks on the Al-Si alloy, comparing with the single constant current mode. In addition, the results of polarization curves and electrochemical impedance spectroscopy (EIS) tests conducted in 3.5 wt. % NaCl solution revealed that the coatings obtained by sectionalized PEO mode had a higher corrosion resistance and provided better corrosion protection for Al-Si alloy.