摘要
利用虚拟声源和合成孔径聚焦相结合的复合成像技术解决复杂曲面构件超声检测图像中的缺陷位置失真问题。首先,在水浸检测条件下利用128阵元线性阵列换能器中采集曲面构件内部缺陷的B扫描数据。通过相邻阵元界面回波时间差构建虚拟声源,并将其定义为声波在水-构件双层界面上的入射点。然后,根据实际阵元-虚拟声源-聚焦目标三者之间的声传播路径,通过合成孔径聚焦技术将各路阵元的接收信号反推至虚拟声源处进行图像的延时叠加重建,最终获得复杂曲面构件中缺陷的超声图像。结果表明,与传统B扫图像和合成孔径聚焦图像相比,虚拟源-合成孔径聚焦图像能够准确呈现复杂曲面构件的表面轮廓,精确表征构件内部的缺陷位置。
A method combining virtual source(VS)and synthetic aperture focusing technique(SAFT)was applied to solve the position distortion of defect echo in ultrasonic image for the components with arbitrarily shaped.First,the line array transducer with 128 elements was used to collect the raw B-scan signals of the component with arbitrarily shaped under the water immersed condition.Then a series of virtual sources at the two-media interface between water and component were created by the time of flight of two consecutive elements.Secondly,in virtue of the virtual sources,the two-segment sound propagation path from emitting elements to virtual sources and from here to focus points were respectively calculated.Last each point of the imaging region was focused by the delay and sum process of SAFT.The results show,in compared of the traditional B-scan and SAFT image,that the defect location of component is displayed accurately in the VS-SAFT image.
作者
甘勇
陈尧
石文泽
陈果
卢超
GAN Yong;CHEN Yao;SHI Wenze;CHEN Guo;LU Chao(Key Laboratory of Non-destructive Testing Technology,Nanchang Hangkong University,Nanchang 330063,China;State Key Laboratory of Acoustics,Institute of Acoustics,Chinese Academy of Sciences,Beijing 100190,China;Shangrao Normal University,Shangrao 334000,China)
出处
《应用声学》
CSCD
北大核心
2019年第2期173-178,共6页
Journal of Applied Acoustics
基金
国家自然科学基金项目(51705232
51265044
51705231)
声场声信息国家重点实验室开放课题研究基金项目(SKLA201806)
江西省优势科技创新团队专项(20171BCB24008)
南昌航空大学研究生创新专项资金项目(校级项目)(YC2017035)
关键词
曲面构件
超声成像
虚拟源
双层界面
Arbitrarily interface structures
Ultrasonic imaging
Virtual source
Two-media interface
