Anticorrosive performance of epoxy/clay nanocomposites pretreated by hexafluorozirconic acid based conversion coating on St12

作者：Salmasifar A; Sarabi A A^*; Mohammadloo H Eivaz

来源：Corrosion Engineering, Science and Technology, 2015, 50(5): 372-379.

DOI：10.1179/1743278214Y.0000000233

• Epoxy/clay nanocomposites
• Hexafluorozirconic acid
• Conversion coating
• Electrochemical impedance spectroscopy

In this research, epoxy composites were prepared using different loadings (0.5, 0.8, 1, 2 and 3 wt-%) of clay nanoparticles. Fourier transform infrared spectroscopy was utilised to investigate the curing behaviour of epoxy resin. The quality of dispersion and the distribution structure of nanoclays in coating were studied by visual observations and X-ray diffraction in detail. Corrosion resistance behaviour of epoxy coating containing various clay percentages was investigated on steel by electrochemical impedance spectroscopy. Moreover, the modification of substrate was accomplished using conversion coating based on hexafluorozirconic acid. The electrochemical results revealed that the pretreated coating with 3 wt-% nanoclays possesses the best anticorrosive performance (2.5 x 10(8) Omega cm(2)) after 2 weeks immersion in 3.5 wt-%NaCl solution. The morphological properties of conversion coating were observed by a field emission scanning electron microscope. In addition, pull-off technique was employed to measure the adhesion strength of coatings to metallic substrate. Experimental results exhibited that optimum clay loadings and conversion coating impressively increased the corrosion resistance and coating adhesion as well.

• 出版日期2015-8