摘要
玻璃纤维增强复合材料具有耐腐蚀性强、介电性能良好和热性能良好等优良性能,被广泛应用于航空航天、铁道铁路等相关行业。以脉宽调制后的太赫兹脉冲激励源作为输入光源,采用徳拜模型对材料实测太赫兹波段光学参数进行拟合优化,并将其作为材料输入参数应用于时域有限差分方法中。建立了玻璃纤维增强复合材料胶接缺陷的太赫兹脉冲检测模型。基于时域有限差分法,对太赫兹波在玻璃纤维增强复合材料胶接缺陷结构中的传播特性进行了数值仿真分析,重点从时域波形及B-Scan成像两方面分析了太赫兹波在胶接缺陷结构中的传播过程以及高次回波的成因。针对玻璃纤维增强复合材料中存在的脱粘缺陷、分层缺陷进行了诊断分析,1 mm厚玻璃纤维增强复合材料中的脱粘缺陷检测厚度达到20μm;玻璃纤维增强复合材料中厚度为80μm的分层缺陷的检测层数达到两层。所提方法可为基于太赫兹脉冲成像的玻璃纤维增强复合材料胶接缺陷的无损检测和评估提供理论支撑。
Fiberreinforced plastics have excellent properties such as strong corrosion resistance,good dielectric properties,and good thermal properties.They are widely used in aerospace,railway and other related industries.In this paper,the pulse-width modulated terahertz pulse excitation source is used as the input light source,and the measured optical parameters of materials in the terahertz band are fitted and optimized using the Debye model,which are used as the material input parameters in the finite-difference time-domain method.A terahertz pulse detection model for the bonding defects of fiber reinforced plastics is established.The finite-difference time-domain method is used to numerically analyze the propagation characteristics of terahertz waves in the bonding defects of fiber reinforced plastics.The propagation process of terahertz waves in the bonding defect structure and the causes of higher-order echoes are analyzed from the two aspects of time domain waveform and B-Scan imaging.We diagnose and analyze the debonding and delamination defects in fiber reinforced plastics.The thickness of delamination defects in 1 mm thick fiber reinforced plastics can reach 20μm.The number of layers for layered defect detection with a thickness of 80μm reaches two layers for fiber reinforced plastics.The proposed method can provide a theoretical support for the non-destructive detection and evaluation of bonding defects in fiber reinforced plastics based on terahertz pulse imaging.
作者
周桐宇
李丽娟
任姣姣
张丹丹
张霁旸
Tongyu Zhou;Lijuan Li;Jiaojiao Ren;Dandan Zhang;Jiyang Zhang(Key Laboratory of Optoelectric Measurement and Optical Information Transmission Technology of Ministry of Education,School of Electro-Optical Engineering,Changchun University of Science and Technology,Changchun,Jilin 130022,China;National Demonstration Center for Experimental Opto-Electronic Engineering Education,School of Electro-Optical Engineering,Changchun University of Science and Technology,Changchun,Jilin 130022,China)
出处
《光学学报》
EI
CAS
CSCD
北大核心
2020年第12期190-198,共9页
Acta Optica Sinica
基金
吉林省科技发展计划项目(201506230147C)
长春理工大学青年创新基金项目(XJJLG-2018-03)
关键词
物理光学
时域有限差分
太赫兹
无损检测
高次回波
physical optics
finite-difference time-domain
terahertz
nondestructive testing
high order echo
