Estimation of Laser Welding Behaviors of SM45C Steel by Plume Monitoring

With the increased use of lasers in industrial welding, techniques for monitoring and controlling these processes have become increasingly important. Thus, understanding the dynamic behaviors of laser organic plume is very important in welding since laser induced plume has a considerable effect on welding efficiency and material quality. As plume fluctuation was associated with keyhole instability, unstable vapor plume would indicate the process that is unstable and would result in poor welding. An infrared thermo-vision camera can be utilized to compensate for incurrence encountered in real-time monitoring during laser welding. We found that plume instability is closely related with hot cracking and laser welding defects.