论文部分内容阅读
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。
Spherical spectroscopy was used to measure the plasma emission spectrum of a single-pulse laser ablated bronze diamond wheel. The calculated plasma electron temperature under single-pulse laser ablation is about 5220K and the plasma electron density is within 0 ~ 0.35 mm from the surface of the grinding wheel The value is 0.5 × 10 ~ (16) ~ 1.8 × 10 ~ (16) cm ~ (-3). The plasma concentration spatial distribution model and the isothermal expansion kinetic equation of the single-pulse laser ablated bronze diamond wheel were established. The simulation results show that the maximum plasma isothermal expansion rate appears at about 25ns in one pulse time, and the plasma concentration is the largest The value (1.8943 × 10 ~ (16) cm ~ (-3)) appears at 0.05mm from the surface of the grinding wheel, and the plasma shielding effect is small, which can not be considered in actual ablation. The experimental results are basically the same order of magnitude as the numerical simulation results, which verify the correctness of the physical model of plasma. The results of this study can guide the optimization of pulsed laser ablation process.