Study on Monitoring Method for Laser Welding Process by using UV and IR sensors

This paper presents a process inspection technology for laser and laser hybrid welding processes. It proposes a quality monitoring method and the laser hybrid welding system with industrial robot for approving the welding speed and accuracy of conventional spot and laser welding systems. The laser hybrid welding process is consisted of the laser and arc welding process. The hybrid welding system has the cost efficiency of arc welding and good performance of laser welding. The laser generator, arc welding and the industrial robotic systems are consisted of laser hybrid welding systems with monitoring system. The laser hybrid welding system with robot was equipped with a laser head and arc welding gun for laser hybrid welding process. The welding joints are butt and Fillet joints. The welding specimens are made from the steel plate and aluminium plate. The quality of welding specimens is tested by observing the shape of the beads on the plate after hybrid welding. The cross-section of the welded parts is observed by using metallography method. The mechanical tensile test is carried out for analysing the performance of welding strength. The monitoring results of the plasma intensity by using UV and IR sensor are used for finding the correlation with the results of the mechanical and metallurgical test.