为了探索TC4钛合金飞机蒙皮材料的激光切割工艺, 对激光切割过程进行了理论分析并建立了数学模型, 利用ANSYS有限元软件, 对激光切割起始穿孔和切割过程进行了仿真模拟, 得到了一定厚度下钛合金试件合理的穿孔时间、切割过程中温度在板件中的传播规律和不同切割速度下温度场的分布。结果表明, 激光起始穿孔时, 功率为1 000 W时穿孔用时最短, 为0.12 s; 起始穿孔孔径不受激光功率变化的影响; 在功率和光斑直径一定时, 速度越慢越容易切透钛合金板件, 但切缝随切割速度减小而增大。通过对钛合金板进行穿孔和切割试验, 在CCD影像测量仪上观测起始孔及切边形貌可知, 起始孔径是切缝宽度的1.35倍; 切缝从上向下成倒锥形, 且上部精度较高, 下部挂渣大, 进一步说明了切割过程中温度传播规律。这些结论为将激光切割技术应用于飞机蒙皮材料切割加工提供了参考和依据。

In order to explore the TC4 titanium alloy aircraft skin materials of laser cutting technology, the laser cutting process is analyzed theoretically and a mathematical model is established in this paper. The initial perforation and cutting process of laser cutting are simulated by ANSYS finite element software, the reasonable piercing time of titanium alloy specimens with a certain thickness, the propagation rule of temperature in the plate during cutting and the distribution of temperature field at different cutting speeds are obtained. The results show that When the laser starts to perforate, the perforation time of 1000W power is the shortest, which is 0.12s; the perforation aperture is larger and not affected by the power change; the power and spot diameter are constant, the slower cutting speed is easier to penetrate the titanium alloy plate, but the slit increases with the cutting speed decreasing. Through piercing and cutting experiments on titanium alloy plate, the morphology of the initial hole and the cutting edge was observed on the CCD image measuring instrument. It was found that the initial aperture was 1.35 times the width of the cutting edge; the cutting seam is inverted cone from top to bottom, and the upper part has high precision and the lower part has large slag hanging. This further explains the law of temperature propagation in the cutting process. These conclusions provide a reference and basis for the application of laser cutting technology to the cutting of aircraft skin materials.