CO2激光气化切割非金属材料的机制分析

研究了CO2激光气化切割高吸收率非金属材料的机制。基于实验拍摄的前沿形状和切缝形状，经过理论分析建立了激光气化切割非金属材料的三维能量耦合模型，分析了实际弯曲切割前沿和两壁面对激光的反射和能量吸收过程。前沿和壁面的能量吸收主要决定于入射光束的前三次入射(即两次反射)，前沿本身的多次反射增强了前沿底部的功率密度，而壁面的多次反射增强了前沿中下部位的功率密度。正是由于多次反射的存在，使得整个前沿都有功率密度分布。两切口壁面对入射激光有波导作用，入射激光在左右两壁面之间相互反射，朝着切口深部传输，即所谓的“壁面聚焦效应”(Wall focusing effect)。

Mechanism of CO2Laser Cutting Nonmetallic Materials

This paper systematically studies the mechanism of evaporation CO2 laser cutting high absorptive nonmetallic material. Based on the cutting front and kerf shape photographed in the experiment, a three-dimensional energy coupling model for evaporative laser cutting nonmetallic material is established through theoretical analysis and the reflective transmission and energy absorption of laser against real bended cutting front and both two walls are analyzed. The front and wall's energy absorption is mainly determined by the first three incident beams, that is two reflections. The multiple reflections from the front will increase the power intensity of the bottom and the multiple reflections from the wall will increase the power intensity from the center to the bottom. Due to the multiple reflections, the power intensity distributes over the total front. Both two walls will have waveguide effects on the incident light which will mutual reflect against both walls and transmit toward the bottom of the cut, that is so-called “wall focusing effect”.