脉冲能量对不锈钢表面微观形貌影响规律研究

为了研究空气中飞秒激光脉冲能量对不锈钢表面形成周期性结构的影响规律，采用脉宽为50fs、中心波长为800nm的飞秒激光辐射304不锈钢表面，利用扫描电子显微镜观察微观形貌，分析了不同种类波纹的产生机理。结果表明，脉冲能量在0.1mJ~0.3mJ时，表面形成垂直于激光偏振方向的纳米级周期性波纹；脉冲能量在0.4mJ~0.7mJ时，表面有产生平行于激光偏振方向的周期性波纹的趋势；脉冲能量在0.8mJ~1.0mJ时，表面出现明显的平行于激光偏振方向的微米级大尺度周期性波纹，且波纹表面覆盖着与其方向垂直的短周期性波纹。该研究为后续在不锈钢表面制备可控微观形貌奠定了基础。

Study on influence of pulsed laser energy on microstructure of stainless steel

In order to study effect of femtosecond laser pulse energy on the periodic structure of stainless steel surface, the femtosecond laser with pulse width of 50fs and central wavelength of 800nm was used to radiate 304 stainless steel surfaces. Scanning electron microscopy was used to observe the micromorphology and the generation mechanism of different kinds of ripples was analyzed. The results show that with pulse energy from 0.1mJ to 0.3mJ, nanoscale periodic ripple perpendicular to the direction of laser polarization is formed on the surface. With pulse energy from 0.4mJ to 0.7mJ, there is a tendency to produce periodic ripples parallel to the direction of laser polarization. With pulse energy from 0.8mJ to 1.0mJ, obvious micron-scale periodic corrugation parallel to the polarization direction of laser appears on the surface, and the corrugation surface is covered with short periodic corrugation perpendicular to its direction. The study lays the foundation for the subsequent preparation of controllable micromorphology on the surface of stainless steel.