Nanosecond laser texturing with hexagonal honeycomb micro-structure on Titanium for improved wettability and optical properties

Abstract

Nanosecond laser provided an efficient and flexible solution for surface texturing on different metals. In this work, a hexagonal honeycomb model was designed on Titanium by laser processing. The surface texturing experiment was carried out by a nanosecond pulsed fiber laser with different scanning speeds. The Scanning Electron Microscopy and White Light Interferometer were used to characterize the surface morphology and roughness. Besides, the contact angle instrument and the Fourier Transform Infrared Spectrometer were used to obtain the effects of surface modification on wettability and optical properties of the Titanium. The wettability and optical reflectivity of the surface changed by controlling the side length of the hexagonal honeycomb model and the laser scanning parameters. The contact angle reached a maximum of 147.4°, the contact angle hysteresis was found to lie between 1.6° and 7.1°, and the optical reflectance for titanium surface decreased by more than 90% after laser processing. The approach presented in this study provided a feasible and efficient method to improve the wettability and optical absorption of titanium surface.