The effect of surface patterning on corrosion of metals

理解表面能和表面拓扑在天然非润湿表面中的互补作用，导致了许多仿生疏水表面的发展。两种截然不同的现象解释了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，从而增加了固体的总表面积。另一方面，这种“粗糙度”允许在液体下面形成亚稳态气囊，从而导致非均质气-固界面上的部分悬浮液体。基于这种疏水(低或不可湿)表面减小了固体表面与电解液(腐蚀剂)之间的实际接触面积的思想，推导出了一种可能的抗腐蚀方法。这种方法的实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，非均质润湿和由此导致的接触表面的减少应该会导致总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表面形貌，使其能够稳定地捕获空气/蒸汽。*拟议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。主要的重点将是开发包含0.1至100微米尺度的结构的结构化表面。建议的表面形貌将通过使用激光烧蚀和深度反应离子刻蚀(DRIE)来创建。提出的研究将试图对表面毛化现象提供深入的研究。因此，这项研究有望在现有防腐技术的基础上取得重大进展，增加人们对在广泛应用中采用表面纹理的认识和论证的可行性。

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.*****