20钢板焊缝缺陷的磁记忆检测

Magnetic memory detection in welding joint of 20 steel plate

与磁粉检测和射线检测相比,磁记忆检测灵敏度更高,利用金属磁记忆技术对20钢板的焊缝缺陷进行无损检测评价。研究表明:磁记忆检测法能够有效表征钢板的焊缝缺陷;与磁场强度参数相比,磁场梯度对焊缝缺陷更为敏感,表现为在被测4块钢板的焊缝缺陷处,其磁场梯度的法向分量均出现了明显增加、并呈凸峰状,且在焊缝一些局部应力集中处,也出现了异常磁记忆信号。在实际应用时,可以利用磁记忆检测快速的特点,先对被测构件焊缝的异常信号进行提取,同时与其他无损检测进行比较,有效实现提高缺陷检测准确性与可靠性的目的。

Compared with magnetic particle detection and ray detection,magnetic memory detection is more sensitive.The magnetic memory technology is employed to carry out nondestructive testing and evaluation for weld defects of 20 steel plate.The results show that,the magnetic memory detection method can effectively characterize the weld defects of steel plates.Compared with the magnetic field intensity parameter,the magnetic field gradient value is more sensitive to the weld defects of the four tested steel plates,which manifested as its normal component increases significantly and presents a convex peak,and the abnormal magnetic memory signals also appear in some places of the weld with local stress concentration.In practical application,the rapid characteristics of the magnetic memory detection technology can be used to extract the abnormal signals of the weld seam of the tested components at first,and then compare it with other non-destructive testing methods,to effectively improve the accuracy and reliability of defect detection.