Patterned solid surfaces with wettability contrast can enhance liquid transport for applications such as electronics thermal management, self-cleaning, and anti-icing. However, prior work has not explored easy and scalable blade-cut masking to impart topography patterned wettability contrast on aluminum (Al), even though Al surfaces are widely used for thermal applications. Here, we demonstrate mask-enabled topography contrast patterning and quantify the resulting accuracy of the topographic pattern resolution, spatial variations in surface roughness, wettability, drop size distribution during dropwise condensation, and thermal emissivity of patterned Al surfaces. The method uses blade-cut vinyl mask templates and a commercially available lacquer resin that serves as a polymer resist against etching. Programmable mask templates enable complex patterning of wettability and emissivity contrast with feature sizes down to ∼1.5 mm. As-fabricated patterned samples show a water contact angle (θ) contrast from <5° to 80° between etched and smooth zones, while patterned samples that are further coated with a hydrophobic promoter show θ contrast between 150° and 120° on etched and smooth zones, respectively. In addition to measuring this wettability contrast via contact angle goniometry, we use condensation visualization experiments to study the spatially controlled condensate morphologies and drop size distributions. These condensation studies demonstrate enhanced droplet shedding on the superhydrophobic regions of striped patterned surfaces compared to homogeneous superhydrophobic surfaces. Motivated by the role of thermal radiation in many phase change processes, we use infrared thermography to map topography-mediated thermal emissivity (ε) contrast between etched (ε ≈ 0.65) and smooth (ε ≈ 0.26) regions. Thus, our study provides a route for researchers to readily create complex and scalable topography-patterned Al surfaces for potential applications in vapor chamber thermal rectification, radiative cooling condensation heat transfer, and high-temperature Leidenfrost or film boiling processes.

中文翻译：

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铝表面上启用蒙版的形貌对比


具有润湿性对比的图案化固体表面可以增强电子热管理、自清洁和防冰等应用的液体传输。然而，尽管 Al 表面广泛用于热应用，但之前的工作尚未探索简单且可扩展的叶片切割掩蔽，以在铝 （Al） 上赋予地形图案的润湿性对比度。在这里，我们演示了启用掩模的地形对比图案，并量化了地形图案分辨率、表面粗糙度的空间变化、润湿性、逐滴冷凝过程中的液滴尺寸分布以及图案化 Al 表面的热发射率的结果精度。该方法使用刀片切割的乙烯基掩模模板和市售的漆树脂，用作抗蚀刻的聚合物光刻胶。可编程掩模模板可实现润湿性和发射率对比度的复杂图案化，特征尺寸低至 ∼1.5 mm。制造的图案样品在蚀刻区和光滑区之间显示出从 <5° 到 80° 的水接触角 （θ） 对比度，而进一步涂有疏水促进剂的图案样品在蚀刻区和光滑区分别显示出 150° 和 120° 之间的 θ 对比度。除了通过接触角测角法测量这种润湿性对比度外，我们还使用冷凝可视化实验来研究空间控制的冷凝物形态和液滴尺寸分布。这些冷凝研究表明，与均匀的超疏水表面相比，条纹图案表面的超疏水区域的液滴脱落增强。受热辐射在许多相变过程中的作用的启发，我们使用红外热成像来绘制蚀刻 （ε ≈ 0 之间地形介导的热发射率 （ε） 对比度。65） 和平滑 （ε ≈ 0.26） 区域。因此，我们的研究为研究人员提供了一种途径，可以轻松创建复杂且可扩展的地形图案 Al 表面，用于均热板热校正、辐射冷却冷凝传热以及高温莱顿弗罗斯特或薄膜沸腾过程的潜在应用。