基于频率–相位编码信号激励的焊缝超声检测分析  

Research on weld ultrasonic testing based on frequencyphase coded excitation

作　　者：张佳莹[1] 丛森[2] 刚铁[1] 林尚扬[1,3] 

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 [2]中国工程物理研究院电子工程研究所,绵阳621900 [3]哈尔滨焊接研究院有限公司,哈尔滨150028

出　　处：《焊接学报》2018年第7期7-11,41,共6页Transactions of The China Welding Institution

基　　金：国家自然科学基金资助项目(51575134;51705484;51175113)

摘　　要：焊接结构在工业领域的应用十分广泛,常应用于复杂结构中,对焊接质量要求较高,需要高时间分辨率的超声检测方法检测焊缝内部缺陷.为了提高检测结果的时间分辨率,将雷达领域的编码激励与脉冲压缩技术引入焊缝检测中,提出一种基于幅度加权频率调制的相位编码激励检测方法,该方法的激励信号为幅度加权的线性调频信号与巴克码信号的复合.结果表明,相同带宽下,与线性调频信号和巴克码激励的检测结果相比,所提出的激励方法检测结果的时间分辨率较高,同时,有效降低了调频带宽对检测结果的影响.Weld is widely used in the industry,especially in the complicated structure.High time resolution is needed to measure the position and size of flaw in the weld more accurately.Coded excitation and pulse compression in radar field has been introduced into weld ultrasonic testing to improve the time resolution.Amplitude weighted frequencyphase coded excitation is proposed to obtain good testing results with higher time resolution and lower sidelobe.The proposed excitation signal combines amplitude weighted linear frequency modulation signal and Barker code.compared with LFM,Barker and conventional brief pulse excitation,the results of simulations and experiments demonstrate that,time resolution of the proposed excitation is higher with the same chirp bandwidth and the chirp bandwidth has less impact on the proposed excitation.

关 键 词：超声检测 编码激励 脉冲压缩 线性调频 巴克码 

分 类 号：TG441.7[金属学及工艺—焊接]