面状缺陷超声检测图像的正演合成  

Forward synthesis ultrasonic images for testing a planar defect

作　　者：迟大钊[1] 马石林[1] 于连洋[1] 刚铁[1] 

机构地区：[1]哈尔滨工业大学先进焊接与连接国家重点实验室,哈尔滨150001

出　　处：《焊接学报》2016年第9期9-12,129,共4页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(51375002;51005056);黑龙江省博士后科研启动基金资助项目(LBH-Q13079)

摘　　要：为了辅助焊接缺陷超声检测的逆问题分析,通过建立仿真模型,对面状缺陷的超声检测信号进行仿真预测并对检测图像进行正演合成.首先采用多高斯声束理论对声波在楔块、界面及被检测试件中的传播过程进行描述;其次采用Kirchhoff近似理论描述声场和面状缺陷的作用结果,制作了底面开口槽作为面状人工缺陷,并进行超声检测.同时对人工缺陷超声检测的一维信号进行仿真预测,并正演合成二维图像.将实际检测结果和模拟仿真结果进行比较,验证仿真模型对检测结果预测的有效性.结果表明,正演合成图像和实际检测图像具有很好的一致性,所建立的仿真模型可辅助焊接缺陷超声检测逆问题分析.In order to solve inverse problem of non-destructive weld defect testing,ultrasonic signal for a planar defectis simulated and the images are forward synthesized. Based on Multi-Gaussian Beams theory,ultrasound propagation behaviors are described. It includes in the probe wedge,wedge-testing piece interface and the testing piece. Based on these,an inspective model is established by employing Kirchhoff approximation theory. A bottom surface broken slot used is fabricated and the artificial planar defect is tested using ultrasonic method. Using the model,ultrasonic A-scan lines are simulated and D-,B-scan foreground images are synthesized. The experimental results show that the simulated dada are in better accordance with the measured ones. Forward synthesis can do help to optimize the testing parameter and solve inverse problem of non-destructive characterization.

关 键 词：超声检测 仿真 正演合成 面状缺陷 

分 类 号：TG441[金属学及工艺—焊接]