碳纤维增强复合材料褶皱缺陷的超声成像  

Ultrasonic imaging of wrinkles in carbon-fiberreinforce-polymer composites

作　　者：张海燕[1] 宋佳昕 任燕 朱琦 马雪芬[3] Zhang Hai-Yan;Song Jia-Xin;Ren Yan;Zhu Qi;Ma Xue-Fen(School Institute for Advanced Communication and Data Science,School of Communication and Information Engineering,Shanghai University,Shanghai 200444,China;School of Mechatronic and Automation Engineering,Shanghai University,Shanghai 200444,China;School of Mechanical Engineering,Shanghai Dianji University,Shanghai 201306,China)

机构地区：[1]上海大学通信与信息工程学院,上海先进通信与数据科学研究院,上海200444 [2]上海大学机电工程与自动化学院,上海200444 [3]上海电机学院机械学院,上海201306

出　　处：《物理学报》2021年第11期101-108,共8页Acta Physica Sinica

基　　金：国家自然科学基金(批准号:11874255,11904223)资助的课题。

摘　　要：碳纤维增强复合材料在制造和使用过程中会产生褶皱,褶皱缺陷的存在使得纤维层起伏不平,超声波传播至纤维界面时不同声束方向的声能量存在差异.针对此问题,提出一种基于声束指向性函数校正的全聚焦阵列成像方法:制备了含褶皱缺陷的碳纤维增强复合材料试样,建立超声阵列数据采集实验系统,捕获全矩阵数据;考虑超声发射/接收阵元不同声束方向的声能量差异,提出全聚焦成像方法的校正模型;将校正前后的全聚焦成像结果与试样的实物图和光学显微镜图像进行对比分析.实验结果表明:基于指向性函数校正的全聚焦成像方法能够有效降低背景噪声,恢复出被检试样的褶皱缺陷和铺层结构等细节信息,为碳纤维增强复合材料褶皱缺陷的精确表征提供了理论指导.Carbon-fiber-reinforced-polymer(CFRP)composites are widely used in aerospace,automobile and other industries because of their excellent performances.However,wrinkles will be formed during the manufacturing and service life process of composites,which is detrimental to the fatigue limit and tensile strength.Due to the fiber waviness,the presence of such defects leads to the acoustic energy difference in different beam directions during ultrasonic nondestructive testing.The directly obtained imaging amplitude cannot characterize the wrinkle properly.In order to solve this problem,the total focusing method(TFM)imaging combing the acoustic beam directivity function correction is presented.Firstly,the longitudinal wave signal is excited by an ultrasonic phased array,from which the echo data is collected by full matrix capture(FMC)in both the healthy and defected samples prepared.Then,considering the difference in acoustic energy from different beam directions of each ultrasonic transmitting/receiving array element,a correction TFM is proposed.Finally,the echo signals are post processed while the results are compared with the optical images.No wrinkle information can be indicated from the direct TFM imaging.In contrast,the wrinkles and layerup information can be recovered from the corrected TFM imaging with an improved signal-to-noise ratio and resolution.Furthermore,owing to the directivity function,the near-surface noise can be effectively reduced and the near-surface fibrous layer information is restored.This method paves the way for the accurate,quantitative and rapid characterizing of wrinkles in real CFRP structures.

关 键 词：超声相控阵 褶皱缺陷 全聚焦成像 指向性校正 

分 类 号：TB33[一般工业技术—材料科学与工程]