The effect of surface patterning on corrosion of metals

了解自然非润湿表面的表面能和表面拓扑结构的互补作用，导致了许多仿生疏水表面的发展。两种不同的现象解释了所观察到的疏水性的性质。一方面，这种表面的粗糙度显著增加，这增加了固体的总表面积。另一方面，这样的“粗糙度”允许在液体下方形成被捕获的亚稳态气穴，这导致在非均匀气固界面上部分悬浮的液体。基于这样的疏水性（低或非疏水性）表面减少固体表面与电解质（腐蚀剂）之间的实际接触面积的想法，推导出对抗腐蚀的可能途径。这种方法的本质是在固液界面实现稳定的非均相润湿。由于腐蚀现象的表面性质，非均匀润湿和由此导致的接触表面的减少应导致整体腐蚀速率的显着降低。在亲水性材料上形成异质界面的挑战在于设计可导致稳定的空气/蒸汽截留的表面形貌。*该研究的主要目标是开发人工表面纹理来控制金属表面的腐蚀。主要重点将是开发包含0.1至100微米尺度结构的结构化表面。建议的表面形貌将通过使用激光烧蚀和深反应离子蚀刻（DRIE）创建。拟议的研究将试图提供深入研究的表面纹理现象。因此，该研究通过增加对在广泛应用中采用表面纹理的理解和证明其可行性，有望在腐蚀防护方面对现有技术取得重大进展。*

Understanding the complementary roles of surface energy and surface topology in natural nonwetting surfaces has led to the development of many biomimetic hydrophobic surfaces. Two distinct phenomena explain the nature of the observed hydrophobicity. On one hand, the roughness of such surfaces is significantly increased, which increases the overall surface area of the solid. On the other hand, such “roughness” allows for the formation of metastable air pockets trapped below the liquid, which results in partially suspended liquid on heterogenous air-solid interface. Based on the idea that such hydrophobic (low or non-wettable) surfaces reduce the actual contact area between the solid surface and the electrolyte(corrosion agent), a possible approach to combat corrosion was deducted. The essence of such approach is to achieve stable heterogeneous wetting at the solid-liquid interface. Due to the surface nature of the corrosion phenomenon the heterogeneous wetting and the resulting reduction in contact surface should lead to a significant reduction in the overall corrosion rate. The challenge in forming heterogeneous interfaces on hydrophilic materials lies in designing surface topographies that will lead to stable air/vapor entrapment.***The main goal of the proposed research is to develop artificial surface texturing to control corrosion on metallic surfaces. The primary focus will be on developing structured surfaces containing structures on a scale of 0.1 to 100 microns. The suggested surface morphologies will be created by using laser ablation and Deep Reactive Ion Etching (DRIE). The proposed research will attempt to provide in-depth study of the surface texturing phenomena. Thus, the research promises a major advance on prior art in corrosion protection by increasing the understanding and demonstrating the feasibility of adopting surface texturing in wide range of applications.*****