5A02铝合金表面微纳结构的制备及防腐行为研究

通过低成本的酸刻蚀、表面钝化处理在5A02铝合金基体表面构筑出二元微米级多孔梯田及絮状纳米粒子层结构,研究了该结构经氟硅烷化低表面能处理后的润湿及抗海水腐蚀特性。结果表明,制备表面获得了优异的超疏水特性,其水滴接触角为156.1°,接触角滞后为1.5°。通过电化学测试进一步表明钝化絮状纳米粒子层及超疏水膜层结构有效抑制了基体电化学腐蚀所必需的阴极和阳极反应,同时阻断了腐蚀介质与基体的接触,最终达到铝合金板表面腐蚀防护的目的,对拓宽铝合金材料的工程应用具有深远的意义。

Fabrication of Micro-Nano Structures on 5A02 Al alloy Subatrate and the Anti-Corrosion Property

This work has developed a low-cost method to render 5A02 Al alloy substrate superior anti-corrosion property with the acid etching, passivation treatment and fluoroalkyl-silane modification. The micro-nano structures were constructed with the micro-scale porous terraces and nano-scale flocculent layer by optimizing the hydrochloric acid etching and potassium permanganate passivation conditions. After the fluoroalkyl-silane modification of the fabricated aluminum surface, a superhydrophobic surface was attained with a water contact angle of 156.1°and a contact angle hysteresis of 1.5°. Meanwhile, the electrochemical tests showed that the fabricated micro- and nano-scale hierarchical structures could inhibit the anode and cathode reaction of the electrochemical corrosion and impede the contact between the substrate and the corrosion medium. As a result, the anti-corrosion property of the fabricated surface was finally improved, which can broaden the application fields of aluminum with important engineering significance.