摘要
超声波兰姆波是钢材结构测查和无损检测领域常用的超声波之一,因超声兰姆波其传播距离长、点对点的检测可承载整体结构信息而被广泛使用。焊接板焊缝由于焊接应力等力学参数的变化,往往会容易产生裂纹等缺陷而导致难以检测,因此,通过有限元模拟可以研究兰姆波在焊接角焊缝结构中的传播机制以及损伤与兰姆波之间的相互作用,通过设置压电陶瓷模型中激励信号的激励源,通过激励源将信号发出,由于信号在传递时会出现重叠、折射等一些不确定因素影响,采用设置等距双接受点的方式进行信号接收,得出超声兰姆波在焊接角件未碰到损伤时延设置路线均匀水平传播,其传播机制遵循兰姆波频谱图,其幅值强度与周期稳定,可以通过设置可接收的信号来比较不同裂纹深度对检测的影响,得出幅值与其裂纹深度成正比的规律,超声兰姆波的波包返回稳定,通过幅值可以推算其飞行时间。当损伤深度变化时,随着深度的变大超声兰姆波的幅值会加大,最后趋于一个极大值,这为损伤定位方法的研究打下坚实基础。
Ultrasonic Lamb waves are one of the commonly used ultrasonic waves in the field of steel structure inspection and non-destructive testing,widely used because of their long propagation distance and the ability to carry overall structural information through point-to-point detection.Welded plate welds are prone to defects such as cracks due to changes in welding stress and other mechanical parameters,making them difficult to detect.Therefore,the propagation mechanism of Lamb waves in the structure of welded fillet welds and the interaction between damage and Lamb waves can be studied through finite element simulation.By setting up the excitation source in the piezoelectric ceramic model,the signal is emitted through the excitation source.Since the signal will be affected by some uncertain factors such as overlap and refraction during transmission,a method of setting up equidistant dual receiving points for signal reception is adopted.It is concluded that when the ultrasonic Lamb wave does not encounter damage in the welding angle,it propagates uniformly along the set route,following the Lamb wave spectrum,with stable amplitude strength and period.By setting an acceptable signal,the impact of different crack depths on detection can be compared,and a rule is derived that the amplitude is directly proportional to the crack depth.The wave packet of the ultrasonic Lamb wave is stable,and its flight time can be calculated through the amplitude.When the depth of damage changes,the amplitude of the ultrasonic Lamb wave will increase as the depth increases,and finally tend to a maximum value,which lays a solid foundation for the study of damage location methods.
作者
刘本友
谷雨
潘家敬
LIU Benyou;GU Yu;PAN Jiajing(Qingte Group Co.,Ltd.,Qingdao 266106,China;College of Electromechanical Engineering,Qingdao University of Science and Technology,Qingdao 266061,China)
出处
《电焊机》
2024年第6期13-18,共6页
Electric Welding Machine
基金
山东省自然科学基金(ZR2023ME201)。
关键词
超声兰姆波
缺陷
损伤
模拟仿真
ultrasonic lamb wave
defects
damage
simulation
作者简介
刘本友,男,硕士,主要从事车桥设计研发及生产工作;通讯作者:潘家敬,男,博士,副教授,主要从事变极性等离子焊接、焊接物理过程数值仿真等研究。E-mail:panjiajing1234@tju.edu.cn。
