Enhanced Wear Performance of Hybrid Epoxy-Ceramic Coatings on Magnesium Substrates

Abstract

Epoxy-based polymer was deposited as sealing agent on porous anodized coatings prepared by plasma electrolytic oxidation (PEO) to construct multilayered "soft-hard" coatings on Mg substrates. Different thicknesses and microstructures of the top epoxy layer were achieved by employing different dip-coating strategies. Atomic force microscopy, pull-off tests, and nanoindentation tests were conducted to study the surface roughness, the adhesion strength of the epoxy layer, and the mechanical properties of each component in the hybrid coating system. The micropores and other defects on the anodized layers were sealed by the epoxy polymer, which decreased the surface roughness. The dominant abrasive wear behavior of blank PEO coatings was significantly reduced by the epoxy layers, and the wear mechanism of the hybrid coatings was proposed considering both the microstructure of the hybrid coatings and the mechanical properties of the different components in the hybrid system.

Современные Концепции Изучения Процессов Коррозионной Деградации Материалов И Покрытий: Теория, Практика, Методология Исследований

“…Для надежной защиты от коррозионной деградации магния и его сплавов используют плазменное электролитическое оксидирование [49,81,86,88,145,263,283,[543][544][545][546][547][548][549][550], которое позволяет создавать слои широкого спектра по составу, микроструктуре, пористости и шероховатости, изменяя состав водных электролитов и параметры режима ПЭО [40,41,87,96,110,[113][114][115]117,131,284,[551][552][553][554][555][556][557][558][559][560]. Преимущество метода ПЭО состоит в его технологичности, экологичности, а также универсальности.…”

Ca-based sealing of plasma electrolytic oxidation coatings on AZ91 Mg alloy

“…Sealing of the porous layer by post-treatment has been explored as an alternative to improve the long-term corrosion resistance of PEO coated Mg alloy. Sol-gel [12][13][14], epoxy [15][16][17][18] and inorganic coatings [19][20][21][22][23] are examples of strategies aimed at forming additional layers or blocking the coating pores and defects. As a general rule, when compared with organic sealings, inorganic based post-treatments are easier to apply, more environmentally friendly and show better thermal and mechanical integrity [24].…”

Constructing Colorful Surfaces with Mechanical Robustness for Magnesium Alloys via a Reagent-Free Method

“…The mechanical properties can be improved by changing the surface composition and microstructure or introducing the physical barrier coating. Various methods have been successfully carried out, including chemical conversion coating, , plasma electrolytic oxidation, , laser treatment, , vapor deposition, and so on. Therefore, it should be a feasible way to endow the metallic materials with brilliant colors and mechanical robustness by surface treatments.…”