Effect of laser pulses on the surface and structural modification of ablated titanium in a liquid-confined environment

The effect of laser pulses on surface morphology, chemical composition and crystallinity of titanium samples after irradiation in ethanol environment has been investigated. KrF Excimer laser (248 nm, 20 ns and 20 Hz) was employed for this purpose. Targets were exposed for various number of laser pulses ranging from 500 to 2000 in ambient environment of ethanol at a fluence of 3.6 J/cm2. In order to explore the modification in surface morphology, chemical composition and crystallinity, scanning electron microscope (SEM), energy dispersive X-ray spectroscopy (EDS) and X-ray diffraction (XRD) techniques were employed, respectively. SEM analysis reveals the formation of grains. The grain size initially decreases for increasing number of laser pulses up to 1500 and then increases with further increase in number of laser pulses up to 2000. The grain boundaries become diffused with increase in number of laser pulses from 500 to 1500. Further increase in number of pulses, up to 2000, results in much wider and dis...