亚音速切向气流下连续激光对玻璃纤维增强树脂基复合材料的穿孔效应  

Perforation Effect of Continuous Laser on Glass Fiber Reinforced Polymer Matrix Composites Under Subsonic Tangential Airflow

作　　者：陈庚 唐杰 周义青 潘云香 张宏超[1] 李泽文 沈中华[1] 陆健[1] Chen Geng;Tang Jie;Zhou yiqing;Pan Yunxiang;Zhang Hongchao;Li Zewen;Shen Zhonghua;Lu jian(School of Science,Nanjing University of Science and Technology,Nanjing 210094,Jiangsu,China)

机构地区：[1]南京理工大学理学院,江苏南京210094

出　　处：《中国激光》2023年第14期14-21,共8页Chinese Journal of Lasers

基　　金：国家自然科学基金(61805120)。

摘　　要：采用波长为1070 nm的连续激光对亚音速切向空气流下玻璃纤维增强树脂基复合材料(GFRP)的穿孔效应进行了研究。通过实验研究了功率密度(848~1556 W/cm^(2))和切向气流流速(0~1个马赫数)对穿孔形貌、穿孔点温度和穿孔时间的影响。结果表明:切向气流流速为0.5个马赫数(Ma)时靶材穿孔时间随功率密度的增加而减小,最大减小了46%;功率密度为848 W/cm^(2)时穿孔时间随气流流速的增加呈先减小后增加的规律,与无气流(0 Ma)时相比,最大仅减小8%。激光功率密度的增加加速了热解气体的产生,使得孔隙压力升高,促进了靶材的剥蚀。切向空气流对作用过程的影响主要包括:降低树脂基体热解所产生的残炭含量,进而改变靶材吸收方式;产生切向剪切力,加速靶材的力学剥蚀;加速对流换热,降低靶材表面温度。当切向气流速度较小(≤0.4 Ma)时,切向气流的作用主要是促进树脂热解,降低残炭含量,转变靶材吸收方式;当切向空气流速较大(0.8~1.0 Ma)时,气流的冷却作用表现得较为明显。Objective Glass fiber reinforced polymer(GFRP)with excellent wave-transparent properties are the preferred choice for optoelectronic devices and microwave dielectric materials owing to their high strength,light weight,and excellent electrical properties.Traditional cutting techniques for processing GFRP have problems such as severe tool wear,low efficiency,and low accuracy.The application of laser processing can solve these problems and has broader application prospects.However,some problems remain in the processing of reduced materials by a single laser beam,such as the shielding of the subsequent laser by the pyrolysis gas,transformation of the target absorption mode due to incomplete pyrolysis of the residual carbon,and irregularity of the ablation morphology.The laser processing assisted by tangential air flow can solve these problems and improve the efficiency of material processing.In this study,a detailed investigation on the target perforation time,ablation morphology,and temperature distribution on the ablation surface under different power densities and tangential air flow was carried out.These results are helpful for improving the processing efficiency and profile of GFRP.Methods A fiber laser(wavelength of 1070 nm)with a maximum output power of 20 kW was used to interact with the GFRP in a relatively confined metal target chamber.Tangential air flow was provided by an air compressor and flowed out through a nozzle,and the air flow rate was measured using the Pitot tube method.A manometer was used to measure the pressure of the tangential air flow output from the nozzle;therefore,the stability of the air flow was monitored.The range of air flow rate used in the experiment was0-1.0 Ma.The temperature evolution from the front and rear surfaces of the target was recorded using an infrared thermometer imager.The temperature data of the perforation point was extracted to draw a temperature change curve with time,and the perforation time was obtained from the falling edge of the temperature curve.Results and

关 键 词：激光光学 激光损伤 连续激光 玻璃纤维增强树脂基复合材料 切向空气流 穿孔效应 

分 类 号：TN249[电子电信—物理电子学]