超快激光辐照诱导金属钛的变化

为实现对超快激光诱导金属钛改变趋势的定性控制及材料改变范围的定量控制, 开展了飞秒和皮秒脉冲激光分别与金属钛烧蚀的对比实验研究。随后使用激光扫描共聚焦显微镜、X射线光电子能谱和透射电子显微镜分别就激光脉冲时间宽度变化对被烧蚀金属钛的表面形貌与烧蚀深度、化学成分、微结构状态的影响规律进行了分析。研究发现: 随着激光脉冲时间宽度从飞秒增加到皮秒量级, 被烧蚀金属钛的表面形貌质量逐渐变差, 最终烧蚀产物的化学成分愈加复杂, 微结构状态的无定形化程度也随之增加。最终认为伴随激光脉冲时间宽度增加, 金属钛中热累积效应的增强而造成被烧蚀材料内部更为严重的热与机械损伤是导致上述实验现象产生的主要原因。

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.