薄型层压复合材料的大视场激光超声检测研究  

Large-Field Laser Ultrasonic Testing of Thin Layer Laminated Composite Materials

作　　者：曾吕明 龙柏年 廖为圣 程中文 纪轩荣 ZENG Lüming;LONG Bainian;LIAO Weisheng;CHENG Zhongwen;JI Xuanrong(State Key Laboratory of Precision Electronics Manufacturing Technology and Equipment,Guangdong University of Technology,Guangzhou 510006,China)

机构地区：[1]广东工业大学精密电子制造技术与装备国家重点实验室,广州510006

出　　处：《航空制造技术》2023年第22期53-59,共7页Aeronautical Manufacturing Technology

基　　金：国家自然科学基金民航联合基金重点项目(U2133213);国家自然科学基金(51975131,62205070);广东省自然科学基金(2023A1515011620,2022A1515240040)。

摘　　要：层压复合材料由两层或多层同种或异种材料叠压形成,因其优异的力学性能被广泛应用于航空、航天和航海等领域。然而在生产和使用阶段,层间易产生脱黏和分层等缺陷,极大影响构件的稳定性。目前,常用的接触式超声检测法存在盲区大、视场小、伪影多、需水耦合等局限性。结合激光超声与空耦超声的优点,搭建一套由八阵元250 kHz空耦超声换能器组成的非接触激光超声检测系统,对厚度分别为0.8 mm金属–碳纤维和0.3 mm金属–金属的薄型层压复合材料进行检测。系统不仅能清晰显示出样品内部的多个脱黏缺陷,还成功识别出由黏结层的压痕和气泡形成的微空洞缺陷,成像视场和信噪比分别高达220 mm和35 dB,并在与高频相控阵检测和X射线检测对比中展现出优异的成像对比度、分辨率和灵敏度。试验结果表明,开发的大视场空耦激光超声检测系统在大尺寸层压复合材料方面具有广阔的应用前景。Laminated composite materials are formed by laminating two or more layers of the same or different materials.Due to the excellent mechanical properties,laminate composite materials are widely used in aerospace and navigation fields.However,during the production and service stage,defects such as disbond and delamination between,layers have greatly affected the stability of component.Currently,the commonly used contact ultrasonic testing has limitations such as large blind area,small field of view,many artifacts and water coupling.Combining the advantages of laser ultrasound and air-coupled ultrasound,a non-contact laser ultrasonic testing system consisting of eight elements 250 kHz air-coupled transducer is developed to detect thin laminated composite materials with thickness of 0.8 mm metal–carbon fiber and 0.3 mm metal–metal,respectively.The system can not only clearly display multiple disbond defects inside the sample,but also successfully identify micro cavity defects formed by bonding layer indentation and bubbles.The imaging field and SNR are up to 220 mm and 35 dB,respectively.Besides,compared to high-frequency phased array testing and X-ray testing,the system exhibits excellent imaging contrast,resolution,and sensitivity.The experimental results show that the developed large-field air-coupled laser ultrasonic testing system has broad application prospects in the large laminated composite materials.

关 键 词：层压复合材料 空耦激光超声 阵列式空耦超声换能器 大视场检测 缺陷检测 

分 类 号：TB33[一般工业技术—材料科学与工程] TB553[理学—物理]