激光微织构表面水滴撞击动力学行为特性研究

Experimental study on dynamic behavior of laser induced droplet impact on microtextured superhydrophobic surface

为了探究低韦伯条件下,微织构超疏水表面的液滴撞击动力学行为特性,利用激光微织构技术在航空用材Ti 6Al4V试样表面用不同扫描速度的纳秒激光制备出三角纹理微纳织构,借助高速摄像实验平台研究水滴撞击水平表面和倾斜表面动力学行为特性。实验结果表明,水滴冲击平表面高度越高,空气越不容易进入片层,使最大铺展系数增加;与平表面相比,相同高度的斜表面滑移时更多空气进入片层,最大铺展系数最小;其中在扫描速度为100mm/s的工况下,表面凸起占比达到64611,表面纳米颗粒最大,微米颗粒最多,表面的静态接触特性与动态接触特性最优。受表面结构和表面能协同作用共同影响水滴弹离表面的状态。本实验可为航空领域制备超疏水、主动防除冰表面提供一定参考。

In order to explore the dynamic characteristics of droplet impact on micro textured superhydrophobic surfaces under low Weber conditions,the triangular texture micro nano weave is prepared on the surface of Ti 6Al 4V specimens for aerospace applications using laser micro weave technology with nanosecond lasers at different scanning speeds,and the dynamical behavior of water droplets impacting on flat and oblique surfaces is investigated with the help of a high speed camera experimental platform.The experimental results show that the higher the height of the water droplet impact flat surface,the less air enters into the lamella,which increases the maximum spreading coefficient.Compared with the flat surface,more air enters into the lamella when sliding on the slanting surface of the same height and the maximum spreading coefficient is the smallest.Among them,at a scanning speed of 100mm/s,the proportion of the surface bump reaches 64.611%,the surface nanoparticles are the largest,the micron particles are the most,and the static and dynamic contact characteristics of the surface are optimal.The synergistic effects of surface structure and surface energy jointly affect the state of water droplets bouncing off the surface.This experiment can provide a reference for the preparation of superhydrophobic and active anti icing surfaces in the aerospace field.