Metal processing by laser radiation is shown to be a promising way to obtain surfaces with controllable wetting and evaporation characteristics. Such surfaces can be used in designing the modern cooling systems based on phase transitions. However, large-scale applications of metal processing by laser radiation are hampered by the lack of a theory that allows predicting the wetting and evaporation of liquid droplets on modified surfaces. In this work, we study a water droplet behavior during its wetting and evaporation on hydrophilic and hydrophobic aluminum alloy surfaces modified by single nanosecond laser pulses. To predict the wettability of the laser-processed surfaces, we proposed to use the empirical correlation of the contact angle on the surface free energy obtained in terms of dynamic contact angles. We analyzed the applicability of two well-known theoretical models to determine the evaporation rates of droplets on hydrophilic and hydrophobic laser-processed surfaces. The Spalding and diffusive evaporation models can be used for water droplet evaporating from the hydrophilic aluminum alloy surface at a temperature difference between the surface and air in the chamber of 0–6.5 K. At higher temperature difference from 6.5 K to 9 K, only the Spalding model is applicable. In the case of the hydrophobic laser-processed aluminum alloy surface, the mass loss rate of evaporating droplet at the temperature difference range of 0–9 K can be predicted by the diffusive model. In addition, this model was found to be appropriate for predicting the geometric dimensions of a droplet evaporating in a pinned contact line mode on hydrophilic surfaces without heating at any stage of its evaporation. The results of this study can be used to predict the wetting and evaporation characteristics of water droplets on aluminum alloy surfaces modified by single nanosecond laser pulses.

通过激光辐射对金属进行处理是获得具有可控润湿和蒸发特性的表面的有前途的方法。这样的表面可用于基于相变设计现代冷却系统。但是，由于缺乏一种可以预测改性表面上液滴的润湿和蒸发的理论，因此妨碍了通过激光辐射进行金属加工的大规模应用。在这项工作中，我们研究了在单个纳秒激光脉冲修饰的亲水和疏水铝合金表面上润湿和蒸发过程中的水滴行为。为了预测激光加工表面的润湿性，我们建议使用根据动态接触角获得的表面自由能上的接触角的经验相关性。我们分析了两个众所周知的理论模型的适用性，以确定在亲水和疏水激光处理过的表面上液滴的蒸发速率。Spalding和扩散蒸发模型可用于在亲水性铝合金表面与室内空气之间的温差为0-6.5 K的情况下从亲水性铝合金表面蒸发水滴。在6.5 K至9 K的较高温差下，仅适用斯伯丁模型。对于疏水性激光加工的铝合金表面，可以通过扩散模型预测在0–9 K的温差范围内蒸发液滴的质量损失率。此外，发现该模型适用于预测在固定接触线模式下在亲水性表面上以固定接触线模式蒸发的液滴的几何尺寸，而在蒸发的任何阶段均不加热。这项研究的结果可用于预测通过单纳秒激光脉冲修饰的铝合金表面上的水滴的润湿和蒸发特性。