Ultrafast laser-induced changes in titanium

In order to realize the qualitative control of the ultrafast laser-induced changes trend and the quantitative control of the ultrafast laser-induced changes range in titanium, respectively, comparative ablation experiments by femtosecond, and picosecond-pulsed laser with different pulse durations were carried out on titanium. Then the influence of laser pulse duration varying on final surface morphology, ablation depth, chemical composition and microstructural state of the ablated titanium were analyzed by laser scanning confocal microscopy, X-ray photoelectron spectroscopy and transmission electron microscopy, respectively. It is found that, as the laser pulse duration increases from femtosecond to picosecond scale, surface morphology quality of ablated titanium gets worse, chemical composition of final ablation products is more complex and also the microstructural state has a higher degree of amorphization. Finally, it is deduced that the occurrence of all above experimental results can be attributed to the more serious thermal and mechanical damages in material resulted from the enhanced heat accumulation effect in titanium with the pulse duration increasing.