基于空气耦合超声的激光焊缝质量评估

随着激光焊接技术在汽车及轨道交通上的广泛应用，对激光焊缝的无损检测技术要求越来越高. 针对3 mm以下的两层金属薄板激光焊缝为对象，探讨了空气耦合超声检测技术对激光焊缝检测的可能性. 利用数值解析和试验分析两种方法，在空气中对铝板激励兰姆(Lamb)波，通过Lamb波在激光焊缝试件中的传播模拟，分析了激光焊缝的宽度以及焊缝的良否对反射率及透射率的影响，解明了Lamb波在激光焊缝试件中的传播规律. 结果表明，可以利用Lamb波A0模式对激光焊缝的质量进行评估.

Quality evaluation of laser welds based on air-coupled ultrasound

With the wide application of laser welding technology in automobile and rail transit, the requirements for non-destructive testing of laser welds are getting higher and higher. For the laser welding of two-layer metal sheets below 3 mm, the air-coupled ultrasonic testing technology is discussed. The possibility of detecting the laser weld. Using numerical analysis and experimental analysis, the Lamb wave is excited on the aluminum plate in the air, and laser welding is analyzed by the propagation simulation of the Lamb wave in the laser weld test piece. By studying the propagation simulation of Lamb waves in laser weld specimens, The effect of the width of the laser weld and the quality of the weld on the reflectivity and transmittance are analyzed. The results show that the Lamb wave A0 mode can be used to evaluate the quality of the laser weld.