CHANGE OF WETTABILITY OF STAINLESS STEEL SURFACE BASED ON LASER TEXTURING OF RELIEF

The use of hydrophobic metal surfaces in heat and power equipment makes it possible to reduce hydraulic resistance and the rate of formation of deposits during transportation of liquid media, to intensify heat exchange processes. To achieve the hydrophobic state on the surface it is necessary to create a micro-roughness in the form of a multimodal relief and to reduce the surface energy. One of the most promising ways to create structured relief is laser modification of the surface (laser ablation). The paper presents the results of studies to determine the influence of laser energy density on the geometric characteristics of the formed relief and wettability properties of the surface of stainless steel grade AISI 304. It was found that by forming a structured relief with a subsequent decrease in surface energy using a surface-active substance, it is possible to achieve an angle of wetting of 149.6° at the energy density of laser radiation of 200 J/cm2.