Investigation of droplet impact dynamics and antibacterial properties of laser microtextured titanium alloy surfaces

In this paper, the fluid dynamics of microbial droplets impacting titanium alloy microtextures were investigated, with a particular emphasis on the effect of the interaction between the two on bacterial adhesion. Laser treatment produced periodic micropits of different depths on the titanium alloy surface. Afterwards, analytical methods such as scanning electron microscopy, X-ray diffraction, and X-ray photoelectron spectroscopy were used to study the physical and chemical properties of the surface. Droplet impact tests were performed to analyze the changes in the shape of droplets when they impacted microtextured surfaces with different depths at different Weber numbers (We), and the activity of bacteria after droplet impact on the textures and the antibacterial properties of the textured surfaces were evaluated. The results show that laser microtextured surfaces are very effective in reducing the number of bacterial adhesions. In addition, increasing the texture depth and Weber number significantly enhances the antibacterial effect. In addition, numerical simulations were used to study the fluid dynamic parameters that affect the droplet impact process and how they affect bacterial adhesion.