Gao Guangrui, Li Ying, Hu Dan, Xi Zhengping
School of Metallurgy, Northeastern University, Shenyang 110819, China.
Northwest Institute for Nonferrous Metal Research, Xi'an 710016, China.
Materials (Basel). 2018 Feb 7;11(2):254. doi: 10.3390/ma11020254.
Micro-arc oxidation (MAO) ceramic coatings were formed on TC4 alloy surface in silicate and metaphosphate electrolytes based with K₂ZrF₆ for various concentrations. X-ray diffraction (XRD), Scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS) were used to characterize the phase composition, microstructure and chemical compositions of the coatings. The infrared emissivity of the coatings was measured at 50 °C in a wavelength range of 8-20 µm. The microstructural observations all revealed the typical porousstructures. Moreover, adecline in roughness and thickness of the prepared coatings can be observed when the concentration of K₂ZrF₆ increases. Combined with the results of XRD and XPS, it was found that all the oxides existed as the amorphous form in the coatings except the TiO₂ phase. The coatings exhibited the highest infrared emissivity value (about 0.89) when the concentration of K₂ZrF₆ was 6 g/L, which was possibly attributed to the defect microstructure and the optimal role of ZrO₂.
在含有不同浓度K₂ZrF₆的硅酸盐和偏磷酸盐电解质中，在TC4合金表面形成了微弧氧化（MAO）陶瓷涂层。采用X射线衍射（XRD）、扫描电子显微镜（SEM）、X射线光电子能谱（XPS）对涂层的相组成、微观结构和化学成分进行了表征。在50℃下，在8-20μm波长范围内测量了涂层的红外发射率。微观结构观察均显示出典型的多孔结构。此外，当K₂ZrF₆浓度增加时，可以观察到所制备涂层的粗糙度和厚度下降。结合XRD和XPS结果发现，除TiO₂相外，所有氧化物在涂层中均以非晶态形式存在。当K₂ZrF₆浓度为6g/L时，涂层表现出最高的红外发射率值（约0.89），这可能归因于缺陷微观结构和ZrO₂的最佳作用。
