高压Ar气对激光诱导土壤等离子体辐射的增强效应

Enhancement Effect of Argon Atmosphere at High Pressure on Radiation Intensity of Laser-Induced Soil Plasmas

使用高能量钕玻璃脉冲激光器（～30J,0.7 ms）烧蚀土壤样品获得等离子体,通过对等离子体图像和光谱的采集,以及对烧蚀质量的测量,分析了高气压（0.2～1.1 MPa）Ar气环境对等离子体辐射强度的影响.结果表明,随着Ar气气压的升高等离子体的体积被压缩,温度升高,亮度明显增强.在实验条件下,等离子体发射光谱强度随着环境气压上升而不断提高,但是激光对样品的烧蚀质量却逐渐下降.结合实验过程对测量结果进行了适当的讨论.

In the present paper, the effects of argon atmosphere at high pressure（0. 2-1.1 MPa） on the radiation intensity of the plasma induced by a high energy neodymium glass laser （energy -30 J, pulse width 0. 7 ms） were studied by recording the photograph and spectra of the plasma as well as measuring the ablated mass. The experimental results show that the volume of the plasma was compressed, the temperature increased, and the lightness enhanced significantly when pressure was raised. Under our experimental condition, the radiation intensities of the plasmas were enhanced with the increase in the gas pressure; but the ablated mass of the sample decreased. The measured results are discussed, combined with the process of the experiment.