金属增材组件中亚表面缺陷的激光超声合成孔径聚焦成像  

Laser Ultrasonic Synthetic Aperture Focusing Technique for Subsurface Defect Imaging in Metal Additive Manufactured Samples

作　　者：陈佳明 何坤 孙飞扬 章晶 陈星宇 贾康宁 范理[1] 程利平 颜学俊 徐晓东[1] 张淑仪[1] Chen Jiaming;He Kun;Sun Feiyang;Zhang Jing;Chen Xingyu;Jia Kangning;Fan Li;Cheng Liping;Yan Xuejun;Xu Xiaodong;Zhang Shuyi(Key Laboratory of Modern Acoustics,Ministry of Education,Institute of Acoustics,School of Physics,Nanjing University,Nanjing 210093,Jiangsu,China;Avic Xi’an Aircraft Industry Group Company Ltd.,Xi’an 710089,Shaanxi,China;College of Engineering and Applied Sciences,Nanjing University,Nanjing 210093,Jiangsu,China)

机构地区：[1]南京大学物理学院声学研究所近代声学教育部重点实验室,江苏南京210093 [2]中航西安飞机工业集团股份有限公司,陕西西安710089 [3]南京大学现代工程与应用科学学院,江苏南京210093

出　　处：《中国激光》2025年第2期148-156,共9页Chinese Journal of Lasers

基　　金：科技部重点研发专项(2022YFA1404404);国家自然科学基金(52394162,52027803)。

摘　　要：针对亚表面缺陷无法采用传统的光学方法进行检测,以及传统超声在增材制造(AM)过程中检测的局限性等问题,提出使用激光超声的方法开展含亚表面缺陷的AM样品的检测研究。首先建立了全光学、完全非接触式的激光超声扫描系统,通过调整聚焦光斑的尺寸来调制激光超声表面波的波长;其次,利用有限元方法开展了激光超声表面波传播特性研究,分析了缺陷导致的超声模态转换特性,并基于超声表面波与亚表面缺陷的相互作用研究了合成孔径聚焦技术(SAFT);最后,利用SAFT对AM样品中的两个亚表面矩形通孔缺陷(两缺陷设计的埋藏深度均为0.4 mm,尺寸分别为0.3 mm和0.5 mm)进行成像。结果表明,SAFT能够在一次线扫描的数据基础上实现亚表面缺陷的快速成像,所获取的缺陷尺寸与其标定尺寸基本相符,缺陷宽度误差为5%。证明了基于激光超声方法的SAFT在AM样品检测上的可行性,表明激光超声检测技术在AM在线质量分析中具有广阔的应用前景。Objective In the service process,the key components of various mechanical components such as bearings,gears,and cylindrical inner walls are affected by various factors such as static load,impact,fatigue,corrosion,and radiation.Their surface areas are prone to damage defects such as cracks,delamination,and fractures,which adversely affect the performance and structural integrity of the components.Surface defects can be divided into surface defects,which are directly exposed to air,and subsurface defects,which are buried beneath the surface.In contrast to surface defects,subsurface defects cannot be detected using traditional optical and other methods;therefore,an effective non-destructive testing method is urgently required.In addition,additive manufacturing(AM),an emerging manufacturing technology,has the advantages of integrated molding,a short processing cycle,and environmental protection compared to traditional subtractive manufacturing technology,and has broad development prospects in aerospace,nuclear power,medicine,and other fields.However,because of rapid heating and cooling during AM processing,defects such as bubbles,nonfusion,spheroidization,and cracks inevitably occur inside the module,which is a key factor limiting the further application of metal AM technology.Because of the layer-by-layer stacking characteristics of the AM process,a nondestructive testing method that can be applied to a high-temperature environment with high-electromagnetic interference and effectively detect surface and sub-surface defects can improve the yield rate of additive manufactured components and the economic benefits of additive manufactured production.To address the limitations of traditional optical and other methods in detecting subsurface defects and that of ultrasound in detecting additive manufactured components,this paper proposes a laser ultrasound method to detect additive manufactured samples containing subsurface defects.Methods A finite element model is first established to simulate the interaction between las

关 键 词：激光超声 合成孔径聚焦技术 亚表面缺陷 增材制造 

分 类 号：TG115.28[金属学及工艺—物理冶金]