摘要
玻璃纤维增强复合材料作为新型的先进复合材料,具有质量轻、耐高温、耐冲击等特有的优点被广泛地应用在航空军工等领域。然而,在其生产过程中由于制作工艺的影响,使其内部容易产生分层和夹杂等微小缺陷;另一方面,此类复合材料在其生命周期内,由于外界因素如冲击力、高温等干扰,使得材料表面和内部发生灼痕和脱粘等缺陷。缺陷的存在使得作为结构件的玻璃纤维增强复合材料的安全系数降低,因此有必要对材料内部的缺陷进行检测。太赫兹时域光谱技术得益于太赫兹波段的独有优势,作为传统无损检测方式的有效补充,以其瞬态性、低能性以及指纹谱性近年来被广泛地应用在复合材料无损检测领域,可以有效地对缺陷进行无损检测。通过检测结果对玻璃纤维增强复合材料的性能进行评估,然而利用太赫兹时域光谱技术对缺陷检测分析时,发现对缺陷进行层析成像过程有一些随时间扩散的条纹,条纹的存在掩盖了缺陷的形状,对缺陷的清晰识别产生影响,进一步导致对缺陷的漏判和误判。现阶段,对于缺陷层析成像时条纹出现的原因在理论上的分析鲜有研究,该研究提出了应用时域有限差分技术建模分析太赫兹波与玻璃纤维增强复合材料的相互作用机理。建立在0.2~1.5 THz频段范围内的反射式数值模型,通过数值模拟实现了对玻璃纤维增强复合材料内部1、3以及5 mm深度处的缺陷成像,并且发现,当太赫兹波垂直入射到玻璃纤维复合材料表面时,每一深度处的缺陷均可清晰成像,当太赫兹波以1°倾斜角入射到玻璃纤维增强复合材料表面以及玻璃纤维增强复合材料上下表面存在2°倾斜时,材料内部每一深度处的缺陷成像中均出现了交替变化的条纹,验证了出现条纹的原因是由干涉现象引起的。
As a new advanced composite material,glass fiber reinforced composite material has the unique advantages of light weight,high temperature resistance and impact resistance,which are widely used in aviation,military industry and other fields.However,during its production process,due to the influence of the manufacturing process,it is easy to produce micro defects such as delamination and inclusion inside material;on the other hand,in the life cycle of such composites material,due to the interference of external factors such as impact force and high temperature,there are defects such as burning marks and debonding on the surface and inside of the materials.The existence of defects reduces the safety factor of glass fiber-reinforced composites material as structural parts,so it is necessary to detect the defects in the materials.Terahertz time-domain spectroscopy benefits from the unique advantages of terahertz band as an effective supplement to the traditional nondestructive testing methods,terahertz time-domain spectroscopy has been widely used in the field of composite nondestructive testing in recent years because of its transient,low energy and fingerprint spectrum,which can effectively detect defects.The performance of glass fiber reinforced composites material is evaluated through the test results.However,when using terahertz time-domain spectroscopy to detect and analyze defects,it is found that some fringes diffuse with time in the tomography process of defects,the existence of fringes masks the shape of defects,affects the clear identification of defects,and further leads to missed and misjudgment of defects.There is little research on the analysis of fringe in defect tomography in theory.This paper proposes the finite-difference time-domain technology to model and analyze the interaction mechanism between terahertz wave and glass fiber reinforced composites material.A reflective numerical model is established in the frequency range of 0.2~1.5 THz.Through numerical simulation,the defects at the depths of 1,3 and 5 mm in glass fiber reinforced composites material are imaged.It is also found that when the terahertz wave is vertically incident on the surface of the glass fiber reinforced composite material,the defects at each depth can be imaged,when the terahertz wave is incident on the surface of the glass fiber reinforced composite material at an inclination angle of 1°,and there is a 2°inclination on the upper and lower surfaces of the glass fiber composite material,alternating fringes appear in the defect imaging at each depth inside the material,it is verified that the fringes are caused by interference.
作者
牟达
王奇书
崔宗宇
任姣姣
张丹丹
李丽娟
辛胤杰
周桐宇
MU Da;WANG Qi-shu;CUI Zong-yu;REN Jiao-jiao;ZHANG Dan-dan;LI Li-juan;XIN Yin-jie;ZHOU Tong-yu(Key Laboratory of Optoelectronic Measurement and Optical Information Transmission Technology,Ministry of Education,School of Opto-Electronic Engineering,Changchun University of Science and Technology,Changchun 130022,China;National Demonstration Center for Experimental Opto-Electronic Engineering Education,School of Opto-Electronic Engineering,Changchun University of Science and Technology,Changchun 130022,China;Changchun Equipment and Technology Research Institute,Changchun 130012,China)
出处
《光谱学与光谱分析》
SCIE
EI
CAS
CSCD
北大核心
2023年第10期3031-3040,共10页
Spectroscopy and Spectral Analysis
基金
“十三五”装备预研共用技术项目(41423050112)
吉林省科技资源开放共享服务平台与科研条件保障项目(20191004022TC)
吉林省科技发展计划项目(201506230147C)资助。
关键词
无损检测
太赫兹
时域有限差分
缺陷成像
干涉条纹
Nondestructive testing
Terahertz
Finite difference time domain
Imaging
Interference
