基于多模式全聚焦方法不同声束路径下的异型构件焊缝缺陷成像研究

Research on Weld Defect Imaging of Special-shaped Components under Different Sound Beam Paths Based on Multi-mode Total Focusing Method

超声成像中不同的声束发射路径下,利用不同模式的全聚焦算法所得到的图像质量有明显区别,针对异型钩件焊缝缺陷检测方法的选择问题,开展焊缝缺陷的多模式全聚焦成像研究。文中在超声波的多路径及易发生波型转换的特性情况下考虑了8种不同的模式波,通过CIVA仿真,对比分析当发射声束直接打到横通孔左上圆弧与发射声束的一次反射波打到横通孔的左下圆弧时,8种模式波的横通孔全聚焦成像质量。结果表明,声束打到两个不同位置时,横通孔不同模式波的全聚焦成像质量有明显区别。当发射声束直接打到横通孔左上圆弧时,直接模式的成像质量更高;当发射声束的一次反射波打到横通孔的左下圆弧时,半跨及全跨模式成像质量更好。

Under different sound beam emission paths in ultrasonic imaging,the image quality obtained by using different modes of total focusing algorithms is obviously different.Aiming at the selection problem of the detection method of welding seam defects of special-shaped hooks,the research of multi-mode total focusing method imaging of welding seam defects is carried out.This paper considers 8 different mode waves in the case of ultrasonic multipath and prone to wave form conversion.Through CIVA simulation,comparative analysis when the transmitted sound beam directly hits the upper left arc of the horizontal through hole and the first time of the transmitted sound beam when the reflected wave hits the lower left arc of the horizontal through hole,the horizontal through hole of the 8 modes of wave is total focusing method image quality.The results show that when the sound beam hits two different positions,the total focusing method quality of the different modes of the transverse through hole is obviously different.when the emitted sound beam hits the upper left arc of the horizontal through hole directly,the imaging quality of the direct mode is higher;when the reflected wave of the emitted sound beam hits the lower left arc of the horizontal through hole,the imaging quality of the half-span and full-span modes better.