Abstract
Laser irradiation of yttria-stabilized zirconia (YSZ) was performed by ultrashort pulses to investigate the possibility for multiscale surface patterning. The fundamental characteristics of microgrooving and nanoscale periodic structure formation were investigated by the picosecond pulsed fiber laser (1030 nm, 100 kHz). It was found that the laser-induced periodic surface structure (LIPSS) formed inside microgrooves by increasing the number of line irradiations (10 irradiations) and over a large surface area more clearly under low scanning speed (1.0 mm/s). Furthermore, we evaluated the thermally induced phase transformation of YSZ from tetragonal to monoclinic phase. Monoclinic ratio was calculated by using micro Laser Raman spectrometer and it could be restrained by reducing the laser power or the number of irradiations. In addition, contact angle of water droplets on YSZ surface was measured and it was found that generation of LIPSS improved the surface hydrophilicity of YSZ. These results demonstrate the possibility of creating zirconia hybrid patterns with high functionality which may expand the applications of YSZ in industry.
