Hydrophobization of Metal Surfaces

Abstract

This work describes possibility to create texturized surfaces by their modification using laser equipment with the aim to achieve steady heterogeneous wetting regime. Experimental results regarding the influence of laser radiation variables on wetting angle are given for steel (20Kh13) and aluminum (D16T) surfaces. This was aided by variation of main variables of laser impact, namely: radiation power (from 10 to 20 W), laser beam scanning speed (from 100 to 500 mm/s), pulse frequency (from 20 to 80 kHz). Analysis of the results has revealed that the maximum wetting angles for steel and aluminum surfaces are 147.64° and 150.27°, respectively, they have been obtained upon laser texturizing at the same variables of laser radiation. The influence of laser spot diameter on wetting angle has been determined upon impact on steel (20Kh13) surface. This has been aided by lenses the with focal lengths of 163 and 100 mm, their laser spot diameters are 59 and 25 μm, respectively. It has been revealed that, other conditions being equal, the wetting angles are higher at higher laser spot diameter (59 μm).