飞秒激光辐射诱导金属表面微纳结构研究

Micro-and Nano-Structures on Metal Induced by Femtosecond Laser Radiation

通过1 kHz的飞秒脉冲(脉宽130 fs,中心波长800 nm)对厚度为60μm的不锈钢65Mn表面进行飞秒微加工,通过拟合得到65Mn的消融阈值为0.5 J.cm-2。研究了飞秒激光作用下表面形成的多种微结构,其中包括纳米孔及纳米柱状物。同时讨论了激光能量和作用脉冲个数对微结构形成的影响。随着周期波纹结构的形成,发现在各种能量和脉冲个数条件下,周期结构的周期约为入射脉冲的波长。相同的激光功率下,在不同加工速度和加工次数下对不锈钢进行表面微加工,得到了规则的圆孔阵列结构。

In the present study the authors performed surface treatment of stainless steel 65Mn （the thickness is 60 μm） by femtosecond laser （pulse duration 148 fs, wavelength 775 nm）. The single-pulse threshold could be obtained directly to be about 0. 2 J · cm^-2. The authors found that the femtosecond laser produced a large number of micro-structures such as nano-pores and nano-protrusions. Then the authors discussed the influence of pulse power and the number of shots on the formed surface structures. The authors found that with the change in the power and the number of pulses, the period of multiple parallel grooved surface patterns remained unchanged, which is about on the sub-micron level. Finally the authors processed the array of holes and the lines with different speed and number of pulses.