单脉冲激光烧蚀青铜砂轮等离子体物理模型研究  

Research of Plasma Physical Model for Single Pulsed Laser Ablation of Bronze-Bond Grinding Wheel

作　　者：蔡颂[1,2] 陈根余[2] 周聪[2] 明兴祖[1] 

机构地区：[1]湖南工业大学机械工程学院,湖南株洲412000 [2]湖南大学汽车车身先进设计制造国家重点实验室,湖南长沙410082

出　　处：《光学学报》2017年第4期198-209,共12页Acta Optica Sinica

基　　金：国家自然科学基金(51375161);国家科技重大专项(2012ZX04003101)

摘　　要：采用光栅光谱仪测量了单脉冲激光烧蚀青铜金刚石砂轮的等离子体空间分辨发射光谱,计算得到单脉冲激光烧蚀下等离子体电子温度约为5220K,距离砂轮表面0~0.35 mm范围内等离子体电子密度值为0.5×10^(16)~1.8×10^(16) cm^(-3)。建立了单脉冲激光烧蚀青铜金刚石砂轮的等离子体浓度空间分布模型以及等温膨胀动力学方程,仿真结果表明,在一个脉冲时间内,等离子体等温膨胀速度最大值出现在25ns左右,等离子体浓度最大值(1.8943×10^(16) cm^(-3))出现在距离砂轮表面0.05mm处,且等离子体屏蔽作用小,实际烧蚀中可以不予考虑。试验结果与数值仿真结果数量级基本一致,验证了等离子体物理模型的正确性。研究结果对优化脉冲激光烧蚀工艺具有指导作用。The grating spectrometer is used to measure the spatially resolved emission spectrum of plasma in single pulsed laser ablation of bronze-bonded diamond grinding wheel. The electronic temperature of plasma in single pulsed laser ablation is 5220 K by calculation. The electron density is about 0.5 × 10^16-1.8× 10^16 cm^-3 at the range of 0-0.35 mm away from the grinding wheel surface dynamic equation of isothermal expansion are built The spatial distribution model of plasma concentration and the The simulation results show that the maximum isothermal expansion speed of plasma appears approximately at 25 ns during the single pulse time. The maximum plasma concentration of 1. 8943× 10^16 cm^-3 appears at 0.05 mm away from the grinding wheel surface, and the plasma shielding effect is so small that it can be ignored in the actual process. The experimental results have the same order of magnitude with the numerical simulation results, which verifies the correctness of the plasma physical model. The research results offer guidance to the optimization of pulsed laser ablation process.

关 键 词：激光技术 激光烧蚀 等离子体 光谱特性 物理模型 

分 类 号：O436[机械工程—光学工程]